A Healthy Virginia Lawns Program

Transcription

1 A Healthy Virginia Lawns Program Fairfax County Extension Office Government Center Pkwy, 10 th Floor Fairfax, VA (703) Master Gardener Horticultural Help Desk (703) /12/15 REV1

2 Welcome! Welcome to Home Turf, A Healthy Virginia Lawns Program. We hope this booklet provides a simple, straight-forward approach to maintaining your lawn. The following lawn care practices will not only help you produce a healthy turf in the most efficient and cost-effective manner, but they will help protect local water quality and that of the Chesapeake Bay. In Virginia, we rely on reservoir systems, wells, and other sources for our freshwater. In recent years, our previously plentiful clean water supplies have been threatened not only by overuse, but also by contamination. Pollutants are carried down with water soaking through the soil to the water table. Runoff (water that does not soak into the ground) flows over the surface, often taking soil and polluting chemicals with it into lakes and streams. Surrounding land that drains into a particular lake or stream is a watershed. Fairfax County has developed comprehensive watershed management plans for each of the county's 30 watersheds. A watershed management plan serves as a tool to identify and address the issues affecting our environment and to protect and restore the county's streams and other water resources. More information about this project can be found at At the homeowner level, lawns and landscapes may contribute to water pollution when homeowners apply pesticides and fertilizers carelessly. By using pesticides and fertilizers properly and only when necessary and following recommended landscape practices, you can do your part to protect our lakes, streams, and drinking water for the future. Home Turf, A Healthy Virginia Lawns Program is based on the work of turf specialists at Virginia Tech. Their extensive research over many years has allowed us to formulate guidelines specifically for Northern Virginia conditions. Producing a quality lawn in northern Virginia can be challenging. When lawns struggle, the natural reaction by most homeowners is to apply more water and fertilizer; rarely does this strategy work. The first important step in having a healthy, great looking lawn 2 9/12/15 REV1

3 is selecting a grass that is best adapted to our region. Cool-season grasses, like fescue and bluegrass are well adapted across much of the state. Warm-season grasses, like bermuda or zoysia are best adapted to the southern Piedmont and Tidewater regions of Virginia. This handbook will focus on managing cool season lawns (fescue, bluegrass) which are usually green at least nine months out of the year. If your lawn consists of warm-season grasses you will receive additional information with your Nutrient Management Plan that will be mailed or ed to you after we receive the results of your soil test from the soil lab at Virginia Tech. Growing a healthy lawn is a process. Your lawn may need two to three years to reach its full potential after you begin implementing the steps recommended by Home Turf, A Healthy Virginia Lawns Program. Adria Bordas Extension Agent Virginia Cooperative Extension 3 9/12/15 REV1

4 Table of Contents Basics of Cool Season Lawn Maintenance Lawn Care Calendar Soil Samples & Lawn Measurement Your Lawn Spreader Lime Application Fertilizing Your Lawn Watering Mowing Core Aerate Top-Dressing with Compost Overseeding Pest Management How to Read a Pesticide Label Broadleaf Weed Control Crabgrass and Other Grassy Weed Control Insects and Disease Control Pet Damage to Lawns Lawn Moss Groundcovers & Reduce Erosion Interpreting Your Nutrient Management Plan Lawn Treatment Record How to Contact Us Acknowledgements /12/15 REV1

5 Basics of Cool Season Lawn Maintenance SOIL TEST Test your soil test every 2-3 years to determine the ph and nutrient needs of your lawn. LAWN SIZE It is important to measure the actual size of the turf area. Don t guess. ADJUST ph The ideal soil ph for grasses is Adjust the ph by adding lime (to raise ph) or sulfur (to lower ph) according to your soil test results. FERTILIZER Use the fertilizer recommended by Virginia Tech Soil Lab as indicated on your Home Turf, A Healthy Virginia Lawns Program Nutrient Management Plan. Fertilize at a rate of one pound of nitrogen per 1,000 square feet of turf twice in the fall. One-half pound of nitrogen per 1,000 sq. ft. can be applied from May 15 th to June 15 th as an option, especially if you omitted one of the fall fertilizations. (Fertilization dates for warm season grasses differ.) WATER Turfgrass needs at least one inch of water per week during the growing season or it will go dormant. If you choose to water, water early in the day to reduce disease problems. MOWING Cut often, so that no more than one-third of the leaf blade is removed per mowing. Mow at 2-1/2 3 inches, mow higher as the temperatures increase. It is not necessary to bag clippings that are less than one inch. They will decompose quickly and return nitrogen to your soil. If you do bag, your clippings can be composted. Never mow with a dull blade. CORE AERATE Core aerate your lawn annually to improve soil structure and reduce compaction. Be sure to use a core-aerator (one that removes soil plugs and deposits them on the lawn surface) and not a spike-type aerator, which can actually increase soil compaction. TOP-DRESS WITH COMPOST Add ¼ inch of fine textured compost to improve the quality and texture of your soil. OVERSEED When overseeding an established lawn, 2 to 3 lbs. of tall fescue per 1,000 sq. ft. is adequate to thicken up the lawn. For best results, over-seed after aerating and topdressing between September 1 st and September 30 th. 3 9/12/15 REV1

6 BROADLEAF WEED CONTROL Identify the type of weed before you treat your lawn. Hand pull or spot treat weeds rather than making broadcast applications of weed killers when possible. CRABGRASS CONTROL Choose pre-emergent crabgrass herbicides that do not contain fertilizer. Treat in early April. Follow the directions on the bag. If needed, spot treat with a post-emergent if crabgrass is present in summer. DISEASE & INSECT CONTROL Generally, fungicides are not necessary in home turf. Strong turf will outgrow most disease problems. White grubs and sod webworms may damage lawns; if you have a problem, contact us for identification and current control recommendations 4 9/12/15 REV1

7 5 9/12/15 REV1

8 Soil Samples A soil test analysis provides recommendations for the proper ratio of nutrient amendments (fertilizer) and rate of application for both fertilizer and lime for your lawn. When you apply only as much lime and fertilizer as the soil needs at the appropriate times, you are preventing nutrient runoff into surface and ground water, saving money and time, and optimizing the health of your lawn. The results of any soil test are no better than the sample submitted. For reliable results, it is vitally important that the soil sample is taken correctly to accurately represent the soil in your lawn. That s why a Master Gardener volunteer collected several random samples from your lawn to send to the soil testing laboratory at Virginia Tech. Example of a Soil Sample Report 6 9/12/15 REV1

9 In the future, if you wish to collect additional soil samples from your garden or landscape you can pick up Soil Sample Information Sheets and Soil Sample boxes at Fairfax County Master Gardeners Plant Clinics held at local Farmers Markets. A schedule of these clinics can be found at the Master Gardener website under the Plant Clinics tab: The Soil Sample forms are also available at the Cooperative Extension Office located at the address on the front of this booklet. Instructions on proper soil sample collection with the Soil Lab address and fees charged can be found on the Soil Sample Information Sheet. A presentation summarizing the steps in conducting a soil test and how to utilize the test information can be found at For more information about sampling and the Virginia Tech lab, VCE Publication W, Soil Sampling for the Home Gardener can be found at: Lawn Measurement Why are accurate lawn measurements important? Instructions for the use of lawn care products such as fertilizers and herbicides specify an application rate per thousand square feet, so it is important that you know the size of your lawn. One method of measuring and calculating the total square footage of your lawn is to break it up into geometric shapes such as squares, rectangles, triangles and circles. The square footage of each individual area can be calculated and then all areas combined for a total square footage. As a participant of the Home Turf keep it simple + keep it green program, a Master Gardener measured your lawn and this measurement will be included on your Nutrient Management plan that will be mailed to you in a few weeks. Unless you alter your landscape by changing the amount of turfgrass you currently have, this number is what you will use as you apply various lawn care products. 7 9/12/15 REV1

10 Your Lawn Spreader There are two basic types of fertilizer/lime spreaders for use on the home lawn: the drop and the broadcast spreader. The drop type spreader (left side of drawing) "drops" a set rate of fertilizer. This type is best suited for a limited space in order to avoid wide dispersal on sidewalks and driveways. The amount of fertilizer that is spread depends on the opening setting, the type of fertilizer used, and the speed at which the spreader is pushed. Although this type of spreader might work well with small areas, it can be difficult to apply fertilizer evenly and can lead to a striped effect on your lawn as the turf absorbs the fertilizer. The broadcast type, also called the rotary or cyclone type, (right side of drawing), has a rotating disc that "throws out" a circular pattern of fertilizer as it is pushed. There is also a hand-held model of a broadcast spreader that may be suited for smaller areas or areas that have steep slopes where it is difficult to evenly roll a push broadcast spreader. Virginia Cooperative Extension Publication Both drop and broadcast spreaders have opening settings for different fertilizer formulations. The settings are only approximate at best, and it is important to calibrate the spreaders before they are used. A detailed explanation of how to calibrate your spreader may be found at: in the publication titled, Calibrating Your Lawn Spreader. As you determine the correct setting for your spreader, keep in mind that it is advisable to use a conservative setting at first. It is much easier to make more than one pass with the fertilizer spreader than it is to rake up excess fertilizer or lime. Too much fertilizer or lime can be harmful to the lawn. Some brands of fertilizers have setting information on the bag; other brands don't. Since the amount of nitrogen in fertilizers varies, remember that you should follow the application rate given on your customized Nutrient Management Plan. Never leave unused fertilizer in the hopper. Fertilizer salts are corrosive and could ruin the spreader. Be sure to collect unused fertilizer and pour it back into the bag, not on the driveway or road. The spreader should be rinsed thoroughly with water and allowed to dry. Oil the spreader with a light machine oil to prevent rusting and keep the working parts in good condition. 8 9/12/15 REV1

11 Lime Application Many of Virginia's soils are very acidic and probably require a supplemental lime application. Soil testing gives you an accurate reading of your lawn s ph (acidity/alkalinity) level. A diagnosis of your soil s fertility and ph status is quite often the answer to the question, Why did my turf fail? A soil ph of 6.5 is considered ideal for turfgrass. At this ph the grass can best utilize the nutrients applied to the lawn. If the ph is out of the 6.2 to 6.5 range, either higher or lower, grass cannot absorb and use the fertilizer you applied as effectively. In short, you are buying fertilizer and not getting the expected benefits. Apply the recommended amount of lime indicated on your Nutrient Management Plan as soon as possible. Below are some helpful guidelines: Lime can be applied any time of the year, as long as the ground is not frozen. Pelletized lime is the easiest form of lime to apply. Pulverized lime may be used, but due to the powdered nature of this lime it is difficult to apply with any even consistency. Your soil test analysis may indicate that you need Calcitic limestone, which is high in calcium. This is a fairly common limestone and can be found at most stores that sell lime. The other most common recommended lime is Dolomitic lime which contains both calcium and magnesium. The maximum amount of lime per application is 50 pounds per 1,000 square feet. Any lime recommendation over 50 pounds per 1,000 square feet must be applied in no more than 50 pound increments. Subsequent applications should be made about four weeks apart. It is recommended that the soil be tested every two to three years. Applying lime is NOT considered annual maintenance. Do not lime again until the soil has been retested. 9 9/12/15 REV1

12 Fertilizing your Lawn Your soil test report will recommend a fertilizer for you to apply. Your Home Turf keep it simple + keep it green Nutrient Management Plan will give you either a specific fertilizer recommendation or a complete turf type fertilizer recommendation and the quantity and time to apply for best results. Fertilizers are labeled with three numbers, called the analysis, which refer to the percentage by weight of nitrogen (N), phosphate (P2O5), and potash (K2O), respectively. Often called N-P-K, these big three elements are required in fairly large quantities for maximum plant growth. One example of a common fertilizer analysis is , which means the fertilizer contains 16% nitrogen, 4% phosphate, and 8% potash by weight. In a 100 pound bag of , there are 16 pounds of nitrogen, 4 pounds of phosphate and 8 pounds of potash. The balance of the product is the carrier on which the N-P-K hitch a ride. The ratio of N-P-K to one another in a analysis is Similarly, a fertilizer labeled has a ratio of Research indicates that fall, not spring, is the best time to fertilize cool-season grasses like tall fescue. Why? Fertilizing in the fall builds a strong, vigorous root system that allows the lawn to stay greener in the winter, and green-up sooner in the spring without stimulating excessive growth (less mowing!) that is susceptible to disease. Strong roots also produce a denser, thicker turf that helps crowd out weeds. For cool season grasses you should fertilize twice in the fall and at a half rate in the spring between May 15 and June 15. Heavy fertilization in the spring encourages top growth at the expense of root growth. Spring fertilization often leads to fungal growth in turf. Cool season grass should never be fertilized in the summer. 10 9/12/15 REV1

13 Watering Irrigation is an all or nothing proposition. To keep your lawn green during a hot, dry summer, you need to water deeply, consistently and regularly as conditions require. The other option is to not water at all and let the grass go dormant. It should recover and turn green again in the fall (or with cooler temperatures and adequate rainfall). Do not fertilize or mow a dormant or moisture-stressed lawn. In general, applying one inch of water per week is the recommendation when there is insufficient rainfall during summer drought. Calibrate your irrigation system by placing a shallow pan, or a tuna fish can in the sprinkler pattern to determine how long it takes to collect one inch of water. Set your sprinkler system according to this time. You may need to measure each area separately if your system is divided up in dissimilar sizes. Tips for better watering Light, frequent irrigations produce shallow, weak root systems. The shallow root system prevents efficient use of plant nutrients and water in the soil. Roots generally grow where the soil is moist, and some turfgrass roots do seek out water deeper in the soil as the surface moisture is depleted. Therefore, it is better for your lawn to apply more water less frequently. Applying one inch of water is often difficult to achieve in a single watering given the slow infiltration rate on most Virginia soils. Therefore, smaller amounts of water applied every three to four days may be required to allow water to enter the soil without causing runoff. Water is best applied early in the day (5:00 a.m. to 10:00 a.m.) when evaporation loss is lowest. Afternoon watering is acceptable but wind may affect uniformity. Night watering minimizes evaporation, but may increase fungal diseases. Also, consider that numerous automatic sprinklers all running during periods of high household use (early morning) may place extreme demands on a community's water system. If you are selecting portable, above-ground sprinklers, look for sprinklers that keep water close to the ground rather than sending a fine mist or spray high into the air. This will help reduce evaporation as well as keep the water on the lawn. Water the lawn, not driveways, sidewalks, or roads, by adjusting sprinkler heads. 11 9/12/15 REV1

14 Mowing Be sure your mower blade is sharp. Dull mower blades tear and damage leaf blades, which can then lead to disease or insect attack. On average, most homeowners in Virginia should plan on sharpening and balancing their blades at least 3 times during the growing season. Mow your grass at the right height during the summer. Longer grass blades increase the depth of the root system, shade the soil, and help drought tolerance (see following table). Kentucky Bluegrass = 2-3 ½ Tall Fescue = 2 ½ - 3 Perennial Ryegrass = 2-3 ½ Creeping Fescue = 2-3 ½ Mowing at the higher level during the summer prevents your turf from drying out as easily, and suppresses germination of weed seeds. Regular mowing at the low end of the recommended range (2 inches) in the spring and fall promotes tillering of new stems, increasing grass density. Remove no more than 1/3 of the leaf blade at each mowing. Consider leaving your grass clippings on your lawn. Lawn clippings are 80 to 85% water and can contain 4% N, ½% P, and 2% K. Think of grass clippings as free fertilizer. They decompose quickly and return nutrients to your lawn. Clippings do not contribute to thatch buildup. Tall fescue grasses do not develop thatch layers. A helpful podcast entitled Mow Like a Pro was created by Mike Goatley, Extension Turfgrass Specialist at Virginia Tech, and can be found at: The podcast lasts approximately 5 minutes. A quick note about fuel: Consult the owner s manual for your lawn mower for specific instructions, but in general, using old gasoline or a blend with ethyl alcohol (i.e. ethanol) may cause problems. Old gasoline becomes corrosive, and particles of sticky, gummy residue form. Ethanol further complicates the chemistry of gasoline and causes it to absorb moisture from the air. Fuel filters, fuel lines, and carburetors may be detrimentally impacted. There are fuel additives available to help counteract these problems. 12 9/12/15 REV1

15 Core Aerate Under certain conditions, such as high clay content or heavy traffic, soil can become compacted, making it very difficult for turfgrass roots to survive. Under compacted conditions, the mineral particles that make up the soil are pressed tightly together, preventing oxygen, water, and nutrients from reaching the roots. The effects of compaction can be reduced greatly by core aerating the lawn. A core aerating machine pulls plugs of soil out of the ground and deposits them on top of the lawn. The holes created provide a means for oxygen and water to penetrate to the root zone of the turf, greatly stimulating the growth of new roots. Core aeration is very disruptive to surface smoothness and should not be done after temperatures warm to levels where the grass will likely be under stress. Fall is the best time to aerate your lawn, but if you have never aerated you may wish to aerate your lawn in the spring. The soil should be moist, but not wet. If rainfall has not been adequate, irrigate the lawn (applying one inch of water) a couple of days before aerating. After aerating, allow the removed plugs to dry in the sun. Then rake or break them up if necessary. If you plan to over-seed, core aeration is a must to disturb the soil surface and ensure good seed to soil contact. Aerators can be rented at many hardware stores, or you may wish to contract this job out to a landscape company. 13 9/12/15 REV1

16 Top-Dressing with Compost After aerating, it is a good idea to top-dress your lawn with a layer of fine-textured compost, about a quarter of an inch deep over the entire lawn. Compost works to: Improve soil texture and structure Enhance microbial activity for a healthy ecosystem Helps soil retain moisture and nutrients Helps soils resist compaction How to Top-Dress with Compost 1. Use Fine-Textured Compost Start with good, fine-textured compost. All garden centers carry good, bagged compost that is ready to use; you can even use seed topper. Compost can also be bought in bulk if you have a large lawn. You can also use your own homemade compost if you have it around. Just as long as it is fine-textured so it will rake out evenly without leaving clumps. 2. Spread the Compost You can use a shovel or just start dumping the compost out around your lawn. 3. Rake It Out Evenly With a flexible, garden rake, spread the compost out over your lawn to about ¼ inch thick. You want a fairly thin layer. Don't apply a thicker layer thinking that more is better, because that can cause problems, like smothering your grass. A thin layer will break down quickly releasing its nutrients into the lawn. When you're done raking you shouldn't see that much compost showing. 14 9/12/15 REV1

17 Overseeding The best time for lawn renovation to address bare spots or thinning turf is late summer to early fall. Spring seeded turf often suffers from the heat and drought of summer. Fall seeded grass has time to become established before the onset of summer extremes and weed competition. For the most effective germination rate, it is best to overseed your lawn after aerating and top-dressing with fine textured compost. Select the best turfgrass. The primary cool-season species (e.g. Kentucky bluegrass, tall fescue, fine-leaf fescues, and perennial ryegrass) are best adapted to Northern Virginia. A list of the best adapted cultivars for the state can be found in the publication Virginia Turfgrass Variety Recommendations at CSES-17_pdf.pdf. This publication provides information regarding the most current research on turfgrass varieties tested at sites in both Virginia and Maryland. These select grasses are not likely to be available at the garden centers of large retailers. Your choice will be to find these products in a specialty nursery or match this list the best you can at the garden centers of large retailers. Fortunately, most of the cultivars being sold at the garden centers of large retailers are still quality grasses that will likely perform satisfactorily. After planting seed, irrigate lightly and frequently until seed germination is complete. Avoid excessive amounts of water because this could wash away or drown the seed. As establishment progresses, gradually cut back on the amount of water applied in order to start promoting a deep root system. How to read a Seed Label: A picture of a typical label found on a bag of grass seed is shown on the following page. 15 9/12/15 REV1

18 Greenviewfertilizer.com Key to diagram: 1. Grass seed product name. 2. Pure grass seed. The percentage by weight of grass seed that is in the bag. 3. Other crop seed. The percentage by weight other than the pure grass species or varieties labeled, but not considered as weed seeds. If "other crop seed" is over 5% of total weight, they must be listed by name. 4. Weed seed. The percentage by weight of weed seeds in this lot. 5. Inert matter. The percentage by weight of material that will not grow. 6. Noxious weeds. If the product contains seeds that are considered noxious weeds as defined by your state these would be listed on the tag. 7. Address. The address of the company providing the grass seed. 8. Origin. State in which the grass seed was grown. 9. Lot number. Each lot of grass seed is uniquely numbered. This number appears on all documents so that it can be traced back to its origin. 10. Test date. Actual month and year this lot of grass seed was tested for germination. 11. Germination. The percentage of pure grass seed that will germinate in a controlled lab. 16 9/12/15 REV1

19 Pest Management The best way to minimize pests is to maintain a healthy, dense turf. You can achieve this by following sound management programs based on the principles previously discussed and by buying the correct turfgrass for the situation. The seed of many cultivars of tall fescue and perennial ryegrass is marketed as "endophyte enhanced." This means that the seed you are purchasing contains a living fungus that is highly desirable! We most often think of disease and bad looking lawns when we think about fungi and turf, but in this case the fungus within the seed (and ultimately your turfgrass) helps reduce the likelihood of attack by insect and disease pests (reduce, not eliminate, pest attack). For situations where tall fescue or perennial ryegrass are used, it is well worth paying a few pennies more per pound to purchase "endophyte enhanced" seed. Identify the Problem before Using Pesticides When diagnosing a plant problem, remember that most problems are not caused by insects or disease. Severe cold or heat, waterlogging or drought, lawn mower damage, and carelessly applied herbicides frequently injure plants. Pesticides will be useless for these kinds of plant damage. Be aware that even if an insect or disease is present, that may not be the cause of your plant problem. The original source of damage to your plant may no longer be present. Also, poor growing conditions can make a plant more susceptible to pests and are often the cause of "pest" problems. Although menacing looking, this Assassin Bug is a good bug. Virginia Cooperative Extension Publication If you determine your problem is caused by a pest, identify the insect, disease, or weed before choosing a pesticide. Ask yourself: 1. Is the injury severe enough to require control? If so, what options are available? Is chemical control the best option? 2. Can the pest be controlled by a pesticide at this stage of its life cycle? 3. Is there a pesticide labeled for use on the plant involved and effective against the pest? Often no pesticide is required for proper control; but if needed, the right pesticide must be applied at the right time to control a particular pest. 17 9/12/15 REV1

20 Proper identification of the pest is obviously crucial in determining how (and even if) a treatment is made. Virginia Tech provides numerous resources for the identification of weeds, insects, and diseases. For weed identification, there are two excellent resources available through Virginia Tech websites that serve as "do-it-yourself" programs. The Weed Identification Guide can be found at This website aids in the identification of common weeds and weed seedlings found throughout Virginia. The weed pictures in this guide are arranged alphabetically by common name. More information for turfgrass weeds can be found at Section-6_Turf-4.pdf. Control of Diseases, Insects and Weeds in Lawns is covered in the following sections of the Virginia Cooperative Extension Pest Management Guide, Home Grounds and Animals Lawn: Diseases Lawn: Weeds Even with the best management programs in place, pests will still invade turf periodically. The occurrence of diseases and insects is usually sporadic, but it is highly likely that most lawns will have some level of weed presence. 18 9/12/15 REV1

21 How to Read a Pesticide Label When reading the label look for 1. Poison or Danger, Warning and Caution These words indicate the level of hazard associated with the product in decreasing order of toxicity. Keep in mind any product bearing one of these words pose some degree of hazard worth exercising care. 2. Active Ingredients Active ingredients are the chemicals and their concentrations that are responsible for its pest-controlling properties. Inert ingredients are chemicals that enhance the active ingredient's utility for stable shelf life or ease of use. 3. Target Pests Target pests and application sites tell the user what pests the product controls and where it can be used. If your pest or application site don't match up, don't use the product! 4. Hazards Look at hazards very closely. Language such as toxic to fish or flammable lets you know how to prevent a problem. Don t just read the front of the label, read all the information provided. Virginia Cooperative Extension Publication Precautionary Statements This usually reinforces how to avoid the product's hazards and will indicate medical treatment or antidote. If you need to wear protective clothing or if there's a waiting period before you can safely reenter a treated area it will be noted here. 6. How to Use, Store and Dispose The label gives important mixture directions for concentrates, what equipment is necessary to apply the pesticide and what conditions are required for the product to be effective. Following storage and disposal directions avoids problems after the product has been used. 7. Days to Harvest This part of the label directs food gardeners how long they must wait before picking or eating fruit and vegetables. 8. Manufacturer or Distributor Further information about the product is available from this source. 19 9/12/15 REV1

22 Broadleaf Weed Control Broadleaf weeds fall into two categories: Summer annual broadleaf weeds and winter annual broadleaf weeds. Spring and summer broadleaf weed control: In mature turf, you usually can make applications of broadleaf herbicides as soon as the weed is actively growing. Typically, this will be when air temperatures are higher than 70ºF. Controlling weeds before they flower is an excellent way to keep them from completing their life cycle and producing seed. This strategy applies to either perennial (e.g., dandelions; clover; plantains) or annual weeds. As temperatures warm, the use of many broadleaf herbicides requires extra caution because of the potential for damage to the turf (particularly cool-season grasses) and desirable landscape and garden plants. Pay extra attention to environmental conditions such as wind and relative humidity in the summer because of the potential for off-site movement onto desirable plants. You should often delay broadleaf herbicide treatments until the early fall because of their potential to damage neighboring plants. In spring and early summer, ornamental plants are young and succulent or producing new buds and tissues that are highly susceptible to herbicide vapors. In fall, perennial plants consist mainly of old and tough tissues that are less susceptible to herbicide injury. In addition, susceptible tissues are just weeks away from a killing frost. Thus, herbicide drift is much less visible and problematic in the fall compared to early summer. Proper treatment timing will depend both on the need to control weeds and to prevent damage to desirable vegetation on the lawn border. There are possible pre and post-emergent controls for both summer and winter annual broadleaf weeds that vary depending on the species. Given the vast number of weeds it is best to consult the Virginia Cooperative Extension Pest Management Guide, Home Grounds and Animals at or contact the extension office. Fairfax County Master Gardeners can help identify weed samples at Plant Clinics held at various Libraries and Farmers Markets from May through September. For a list of Plant Clinic locations, go to Weed samples may also be brought to the extension office for identification. Remember to use caution when using any pesticide. Spraying weeds on a windy day can easily cause the spray to drift onto shrubs and flowers and will most often kill them. 20 9/12/15 REV1

23 Crabgrass and Other Grassy Weed Control Crabgrass is the most common summer annual grassy weed. It is best controlled by a pre-emergent herbicide, which is applied before the weed seed germinates. The first application should be made after the forsythias are in bloom, but before the dogwoods are, usually the last week in March or the first week in April. Consult the Virginia Cooperative Extension Pest Management Guide, Home Grounds and Animals at pubs.ext.vt.edu/456/ /section_5_lawn-2.pdf for pre-emergent active ingredients to look for in products available in your local store or nursery. Many products require a second application. Read and follow label directions exactly for season-long control. All of these products, with the exception of Tupersan, will also prevent grass seed from germinating, and should not be applied when over-seeding. Another annual grassy weed, annual bluegrass (Poa annua), can be controlled by a pre-emergent herbicide, but this application is made in late August. Note: This preemergent herbicide will also prevent grass seed from germinating. Perennial grassy weeds, such as wiregrass (common bermuda grass), are not controlled by pre-emergent herbicides. They require a post-emergent application of a non-selective herbicide such as glyphosate (Roundup, Kleenup, etc.). The wiregrass should be actively growing when the herbicide is applied. Results are usually not seen for several days and repeated applications may be necessary. Note: Glyphosate will kill any vegetation it touches, including desirable grasses, shrubs, perennials and annuals. To avoid spray drift, never spray on a windy day. Always read label directions. Control of sedges and "grass-like" plants. Yellow nutsedge is the most common sedge problem in Virginia. Sedges emerge in early summer and are present from June until frost. Most sedges are perennials and enter dormancy during winter. Sedges are not controlled by selective grass killers or preemergence herbicides that are used to prevent crabgrass. Sedges thrive in wet or hot summers and often require more than one herbicide treatment for season-long control. Yellow nutsedge produces small nutlets underground that sprout at some time in the future. It is important to hand pull small populations of sedge plants to reduce production of these nutlets. Hand pulling does not remove nutlets that are already produced, but helps reduce population expansion by preventing mature plants from making more nutlets. Herbicides kill some, but not all, nutlets attached to parent plants. Sedge problems won t be solved in one or two seasons, and require constant vigilance. Try products that have the active ingredient Bentazon or Sulfentrazone + Prodiamine. 21 9/12/15 REV1

24 Wild garlic is another grass-like plant commonly found as a weed in home lawns. Wild garlic sprouts from bulbs in the fall and is most prevalent in winter and early spring. In cool-season turfgrass, wild garlic is often noticed by the "onion" smell that occurs during spring mowings. Wild garlic can be controlled in cool-season turfgrass with postemergent products having 2,4-D as one of the active ingredients. The preferred time to treat is in the fall. 22 9/12/15 REV1

25 Insects and Disease Control As with weeds, always identify insects and diseases before attempting to control them. Fairfax County Master Gardeners can help identify insects and diseased samples at Plant Clinics, or you can submit samples to the Extension office for identification and control recommendations. Physically remove pests when possible. When a pesticide is necessary, choose the least toxic alternative. Don t assume you have grubs, check before you treat. In at least four locations across your lawn, cut three sides of a 1-foot square portion of sod with a spade to a depth of three inches. Roll back the cut out portion, loosen the soil around the exposed roots, and count the number of grubs. If the average number of grubs is greater than six, you may want to treat the lawn with an insecticide labeled for grubs. The larvae of the Japanese beetle are similar to other species of white grubs and have an off-white body with a brown head. They curl into a C-shape when not active. Japanese beetles larvae have a distinctive v-shaped row of spines on the end of the abdomen. Virginia Cooperative Extension Publication Milky Spore is a biological control product containing bacteria that suppresses the population of only Japanese beetle grubs, and not other turf pests in the lawn. Note that use of fungicide or insecticide will render milky spore ineffective. Alternatively, you can apply an insecticide in late-july when the grubs are small. Water in the product with about 1/2 inch of water to move the product through the soil to reach the grubs. Always follow label directions carefully when applying any pesticide. Brown patch is the most common lawn disease in our area. This disease is caused by a fungus that thrives during our humid, warm summers. Leaf blades turn brown and die in patches, but the grass plant usually survives. The grass patches will recover when the weather turns cooler and less humid. A six inch round sample of turf with roots intact can be brought to the Extension office to confirm brown patch. The disease can be controlled with fungicides, but this is an expensive option. You may decide to live with the problem and wait for the grass to recover on its own. It should be noted that fertilization in spring and summer is the main cause of any fungus in our area. 23 9/12/15 REV1

26 Pet Damage to Lawns For many dog owners, having a great-looking lawn just doesn t seem possible. Dog urine and feces can often be a frustrating problem related to lawn care. Small amounts may produce a green up or fertilizer effect, while larger amounts often result in dead brown patches or lawn burn, which are frequently surrounded by a green outside ring. While most burn spots will recover with time and regrowth, burns can be severe enough in some cases to require reseeding or sodding. For homeowners who are also dog lovers, this can present a difficult challenge, especially when one family member prefers the dog and another prefers a well-manicured lawn. An understanding of the interaction between dogs and the lawn can keep the yard at peace, not in pieces. Understanding the Problem The fundamental problem with the presence of urine or feces on the lawn is related to the concentration and nitrogen content of these waste products. Urine, when produced as a waste product in animals, primarily removes excess nitrogen from the body via the kidneys. Urine is a bigger problem for lawns because it is applied all at once as a liquid fertilizer, whereas feces slowly release the waste products over time. Letting feces remain on the lawn for a period of time can smother and kill grass, providing weeds with an opportunity to establish. The primary concern in addressing urine damage to lawns is minimizing the urine concentration added to the lawn at any single time. Female dogs, being less likely to urine mark objects and more likely to squat, are the primary culprits of lawn damage since they will urinate anywhere on a lawn and usually all at once. This results in a single nitrogen dump confined to a small patch of grass. The brown spot that results will often have a green ring around the outside. The nitrogen overload at the center causes the burn, but as the urine is diluted out toward the periphery, it has fertilizer effect. This characteristic brown spot, green ring pattern has been called female dog spot disease by some horticulturists. What About Urine ph & Dietary Supplements? Dr. Allard, a Colorado veterinarian, examined numerous variations in dog urine and the effects on several common lawn grasses. His results support the fact that urine concentration and volume of urine (nitrogen content) had the most harmful effects on lawns. The ph of the urine did not have any variable effect nor did common additives designed to alter the urine ph. Therefore, dietary supplements designed to alter urine ph are not recommended, as they have no known benefit to the lawn and can predispose the dog to bladder stones and infections. 24 9/12/15 REV1

27 Repellents Obviously, fences can be used to keep neighboring dogs from eliminating on the lawn. Unfortunately, no repellents are universally effective although a variety of home remedies have been tried. Hot and bitter products are most likely to have repelling taste or odor properties to dogs. Most repellents function better as taste repellents than touch or odor repellents. Some odor repellents may actually encourage a dog to over-mark the strange smell with their urine. The key to reducing lawn damage is to immediately dilute the urine with water and remove the feces promptly. If you don t have the time to follow your dog around each time he visits the lawn, you may want to consider training your dog to eliminate in a designated area of the yard. Designating an Elimination Area This area would be a landscaped area specifically designed for the dog. It will need a substrate like pea gravel or mulch that the dog finds acceptable and may even include a marking post like a large boulder, bird bath, lawn ornament, or even faux hydrant. Collecting the dog s urine in a cup and using it in this area for several days can provide some odor attractant value to this area. Feces can also be collected and transported to the new, designated area. Consistency is important for at least 2-3 weeks to establish this as a routine, trained behavior; several months may be necessary in some cases. It is very important the dog not be allowed to eliminate anywhere but the designated place during the training process. This could be accomplished by taking the dog out on a leash to the designated spot and rewarding her with a food treat when she eliminates in the appropriate area. It is often easier to train a young puppy to a particular ground texture than an adult dog, but never impossible in any age dog. Many dog owners will also find it helpful to train their dog to an elimination command during this time. A dog can be trained to eliminate on a verbal signal by simply saying the word immediately before he eliminates and rewarding him with a food treat after he finishes. Common commands might include: potty, piddle, do your business or hurry up, etc., and make it quicker to accomplish the task when inclement weather is present or time is short. A little training effort now will pay off in the long run: preserving the looks of your lawn and saving you time in pet clean up perhaps even resulting in a little more time to play fetch with Fido. Information in this publication was taken from the article Dog-On-It Lawn Problems, Updated, which appeared in the June 2002 web issue of Horticulture Update, edited by Dr. Douglas F. Welsh, and produced by Extension Horticulture, Texas Cooperative Extension, The Texas A&M University System, College Station, Texas. 25 9/12/15 REV1

28 Lawn Moss There are thousands of species of moss worldwide. These very simple plants lack the typical leaf, shoot, root, and seed-forming systems of most higher plants; however, they are some of the hardiest living organisms on the planet. Lawn moss can reproduce sexually (spores, etc.) or asexually (breaking off into smaller pieces that divide and multiply), and their numbers can increase rapidly under the right conditions. They are tolerant of extremely low mowing, so regular clipping of the grass will not remove them. It would seem that these plants would not offer much resistance to our efforts to manage or control them, but as Mother Nature often shows, their simplicity in design and function correlates well with their ability to colonize and persist in some of the most inhospitable growing conditions around your property: sidewalks, driveways, and yes the lawn. Why mosses occur It is important to understand that mosses occur when some underlying condition allows them to out compete turfgrasses and other plants. These conditions most frequently are some combination of: 1) Acidic soil conditions. 2) Poorly drained, persistently wet soils. 3) Medium to dense shade. 4) Repeated scalping of turf on uneven terrain. 5) Compacted soils. Steps you can take to reduce the competition from moss If the problems that are limiting the turf or other plant growth are not corrected, any moss elimination or control efforts will be futile. First, identify which of the above factors is likely contributing to the occurrence of the moss. What is your soil ph? If you do not know, then a soil test is required. A soil test is simple to perform and very affordable for the amount of information you will receive regarding lime and nutrient requirements. Next, is the site poorly drained? If so, install drainage or regrade the area to promote water removal. Mosses thrive in these conditions, whereas all turfgrasses struggle. The third factor that likely is limiting the turf is lack of sunlight. Many species of moss are tolerant of dense shade and prefer moist soil in the shaded areas. Removing trees from the lawn would fix the shade problem but this practice is almost never acceptable to the average homeowner. However, simply pruning trees to remove lower limbs or thin the canopy fosters much improvement of turfgrass growing conditions. Any arborist would concede that tree pruning usually promotes healthy trees, so pruning benefits both trees and lawn. 26 9/12/15 REV1

29 If moss occurs in sunny spots, mower scalp may be the culprit. Wide mower decks reduce time on the mower but may contribute to scalping on uneven slopes. Scalping severely weakens turfgrass and allows moss to thrive. Smooth the uneven places in the lawn by topdressing with soil, regrade the area, or use a smaller mower in uneven areas. Compacted soils also give moss a competitive advantage. Use a core aeration machine to alleviate compaction and improve turfgrass growing conditions. You can rent such machines or hire a professional to aerate the lawn for you. Alternatives in moss control/suppression Physically removing moss with a rake is one way to get rid of moss, but it is essentially impossible to get every single piece of this very simple but durable organism. Remember there are plenty of spores already in the soil or that are being moved in by wind or water. Remove all vegetative material that you possibly can, scratch the soil, and reseed with a turfgrass that best fits the site. There are no easy chemical solutions to moss, but there are some compounds that will reduce moss populations with repeated use. It is common for homeowners to attempt moss control with glyphosate, likely our most widely used nonselective herbicide for lawn and landscape use. However, glyphosate does not work on most mosses. Carfentrazone is labeled for moss control in home lawns when applied by licensed lawn and landscape professionals. This product is only labeled for use by professional applicators. There are numerous compounds that suppress moss by acting as desiccants. Ground limestone (at levels of 75 to 100 pounds per 1,000 square feet) and hydrated lime (2 to 3 pounds per 1,000 square feet) are readily available and inexpensive. Other compounds specifically marketed for moss control include ferrous sulfate (commonly called iron sulfate), ferrous ammonium sulfate, and copper sulfate. These products may be found at your local hardware or department store and will specifically mention moss control on the label. You also might recognize these materials as some of the lawn and landscape industry s earliest fungicides. The iron and copper-based materials can be toxic to new turfgrass establishments, so they often must be deactivated by a lime application that counteracts the effects of the metals applied. These desiccants are ideally used winter through spring when the chances for damaging the existing turf are reduced. Carefully follow label directions in order to maximize product effectiveness and turf safety. Remember if the problems limiting turf growth are not solved, the moss will bounce right back following treatment. The moss is not driving out the turf, but the absence of turf vigor allows the moss to expand its area. An alternative to eradicating moss is to embrace it. Removing the conditions that favor moss over turf may timely and expensive. More information on growing a moss lawn the publication entitled Lawn Moss: Friend or Foe? can be found at: go to pubs.ext.vt.edu/430/ / _pdf.pdf. 27 9/12/15 REV1

30 Groundcovers Ground covers are low-growing plants that spread quickly to form a dense cover. They add beauty to the landscape and, at the same time, help prevent soil erosion. Grass is the best known ground cover, but grass is not suited to all locations. Other ground cover plants should be used where grass is difficult to grow or maintain. Unlike grass, most ground cover plants cannot be walked on. They can be used effectively to reduce maintenance work and to put the finishing touch on any landscaping project. Location Ground covers can be found to fit many conditions, but they are used most frequently for the following locations: Steep banks or slopes Shady areas under trees and next to buildings Underplantings in shrub borders and beds Where tree roots grow close to the surface and prevent grass from growing Very wet or very dry locations When planted under trees, ground covers reduce the possibility of mower damage to the base of the tree. Some ground covers may be used to protect the roots of shallowrooted trees. They shade the soil and keep it from drying out rapidly. Some ground covers don't require as much moisture and nutrients as grass. Therefore, they are in less competition with trees and shrubs. Reduce Erosion Because soil sediment makes up most of the pollutant carried by runoff and most of the phosphates and pesticides entering Virginia's waters are attached to this sediment, controlling erosion will help control water pollution. Landscaping can help control erosion by holding soil in place and reducing runoff. Plant a vigorous ground cover on steep slopes to reduce erosion and runoff. Turfgrass is often impractical here because mowing is difficult and dangerous on steep terrain. Build terraces or a retaining wall on slopes. These can intercept runoff, giving water time to soak into the ground, and can make attractive planting beds. Be aware that altering the soil level near established trees can seriously damage their root systems. Don't leave soil bare over the winter. Plant a cover crop, such as annual rye, or place mulch on the soil. 28 9/12/15 REV1

31 Interpreting Your Nutrient Management Plan In a few weeks you will receive a Nutrient Management Plan customized specifically for your lawn using the measurements taken by a Master Gardener and with results of the soil test completed at the soil lab at Virginia Tech. Your plan will document the square footage, area tested and the ph of the soil test, followed by the fertilizer recommendation. Fertilizer recommendation: Fertilizer recommendations by the soil lab are given in ratios. Your Nutrient Management Plan will give you specific formulations (e.g , ) found at local stores, and the number of pounds of fertilizer needed for each application. Simply buy the size bag or combination of bags, in pounds, closest to your recommendation. For example, if your recommendation states you need 28.2 pounds per application in the fall, you can buy a 55lb bag of fertilizer and use half for the first application and half for the second. To prevent burning your lawn, it is better to use less, versus more, fertilizer. Lime recommendation: If you need lime, you will be given both the total pounds of lime and the number of 40 pound bags of lime needed for each application. You can use lime in pellet or pulverized form. Pelletized lime is easier to apply and makes less mess. Organic Matter: This is the number one lawn amendment to enhance your soil. Apply 1/4 inch of compost annually. This is 1/4 inch measured from your current soil level, not 1/4 inch covering your grass. You should be able to see your grass after compost application. Lawn Treatment Record On the following page you will find a form we hope you will utilize to track the maintenance steps you perform on your lawn. This information will help us assist you in the future should you have questions. Thank you for participating in this program! 29 9/12/15 REV1

32 NOTES 30 9/12/15 REV1

33 Lawn Treatment Record Participant s Name: Square Footage of Turf Area: Soil ph: _ Grass Type: Cool Season (fescue) _ Warm Season (zoysia) _ Mixture Use this form to record every application of fertilizer, lime or pesticide. Please be very specific with weights and fertilizer analysis (three numbers that appear on the front of the bag). See example entries below. Timing makes a big difference! Refer to the lawn care calendar for the proper time to aerate, fertilize, seed or treat your lawn. Avoid applying fertilizers to sidewalks, driveways, and curbs. surfaces, sweep, do not hose, the fertilizer back into the grass. Other recommended practices: Annual core aeration Annual overseeding Correct mowing height Leaving grass clippings on the lawn (grass recycling) If fertilizer gets on hard This will prevent run-off. Date Product or Activity Analysis Amount Applied Comments 8/15/11 Core Aeration n/a n/a rented machine for 1/2 day 9/10/11 Fertilized lbs. 35% W.I.N. 31 9/12/15 REV1

34 How to contact us: Home Turf, A Healthy Virginia Lawns Program You can contact us at fairfaxhometurf@gmail.com. Since the program is comprised entirely of volunteers, we will try to get back to you by the following day. Plant Clinics Fairfax County Master Gardeners host Plant Clinics at various Libraries and Farmers Markets from May through September. For a list of Plant Clinic locations, go to fairfaxgardening.org. Master Gardener Horticultural Help Desk During the growing season (April through October) we are on duty five mornings a week, Monday through Friday, from 9:30 am to 12:30 pm. In November through March, the desk is staffed 9:30-12:30 on Tuesday and Thursday mornings only. Contact us anytime by voice mail at (703) or by at mgfairfax@vt.edu. Fairfax County Extension Office Government Center Prkwy, Suite 1050 Fairfax, VA (703) A few words about who we are Fairfax County Master Gardeners have been serving the community since Through Fairfax County Master Gardeners Association, Inc. (FCMGA), we are a nonprofit organization of volunteers who receive training under the auspices of the Virginia and Fairfax County Cooperative Extension offices. We help provide researchbased horticultural information, tips, techniques and advice to home gardeners in the community. We do this through our plant clinics - held in various locations throughout the county during the months of May through September - and other community service activities, such as this Home Turf program. For more information about our other public services, including our Diagnostic Lab, Speakers Bureau and Help Desk, please check out our website: If you are interested in becoming a Master Gardener, guidelines and contact information are provided in the Contact Us portion of our website. 33 9/12/15 REV1

35 Acknowledgements The Fairfax County Unit of Virginia Cooperative Extension would like to acknowledge the Prince William, Henrico and Chesterfield County Units for their contributions to the creation of the Home Turf, A Healthy Virginia Lawns Program handbook. Special thanks to Phyllis Ingram, editor of Prince William County s Best Lawn handbook for her assistance. Other sources of information for this booklet include: Virginia Polytechnic Institute and State University Virginia State University Virginia Department of Conservation and Recreation Environmental Protection Agency Virginia Cooperative Extension Publications Throughout this booklet are references to Virginia Tech Cooperative Extension publications. They are a great resource and provide valuable information on a variety of topics. The entire list of publications can be found at: For more in-depth information specific to lawns in Virginia, the list of publications can be found at: Another helpful resource is the Turf and Garden Tips publication, which is updated periodically and includes archived editions /12/15 REV1