Season s Greetings. January 2017

Transcription

1 Mesa County Noxious Weed & Pest Management, PO Box 20,000 Department 5087 Grand Junction, CO January 2017 Season s Greetings It is an honor to introduce the first newsletter since I joined Mesa County as Coordinator for the Upper Grand Valley Pest Control District and Noxious Weed Management programs in In the past two and-a-half years I learned more about the region I have called home for 20 years than in all of my time here before that. Discovering new scenery from remote county roads and being involved with various weed and pest mitigation efforts have presented learning opportunities and enjoyment that I did not expect. However, my favorite aspect of holding this position has been the opportunity to meet and work with the many wonderful members of our community. Partners from CSU Tri-River Area Extension, Western Colorado Research Center, Colorado Department of Agriculture, Western Colorado Horticultural Society, the UGVPCD advisory committee members, and each local commercial grower and hobbyist I have met have shown me that with hard work and cooperation, mighty accomplishments are possible. With the hope of carrying my weight in these partnerships and serving the citizens who make my job not only possible but a pleasure, I present to you this newsletter containing new information on issues pertinent to all citizens of the Upper Grand Valley Pest Control District as the fruit industry continues to grow and change, at home & afar. In the past 2 years we have found the pests grape phylloxera and spotted wing drosophila in the valley, which threaten our expanding grape industry and cane fruit growers, respectively. P e s t D i s t r i c t G o a l s 1. C r e a t e a w a r e n e s s o f i n s e c t, p l a n t d i s e a s - e s, a n d w e e d p e s t s. 2. I. D., m a p, a n d m o n i - t o r p e s t i n f e s t a t i o n s w i t h i n d i s t r i c t b o u n d - a r i e s. 3. P r o m o t e l a n d o w n e r r e s p o n s i b i l i t i e s f o r p r o p e r c a r e o f f r u i t t r e e s. 4. C o o r d i n a t e p e s t c o n - t r o l t h r u a n e t w o r k o f p u b l i c a g e n c i e s a n d p r i v a t e o r g a n i z a t i o n s. A new work group combining CSU sponsored research and citizen input to manage cytospora has been developed, the peach mosaic quarantine was lifted in March 2016, and trapping and monitoring efforts for Japanese beetle, western cherry fruit fly, and any new invader that may arrive continue each summer through the CSU Extension entomology program. In 2017, we will have the opportunity to add species to the UGVPCD list for regulation and management funding. Be on the lookout for additional information coming soon, and please contact us any time to contribute your opinion. We will also send our best wishes to Bob Hammon who will be retiring from CSU Extension after nearly 29 years to pursue research and consultation (and vacation!) on his own. Please take some time to read and discuss these topics with your neighbors and friends, and feel free to contact myself or any of the contributing writers should you have questions or would like assistance. Thank you for your continued hard work and stewardship of our wonderful land resources here in the Grand Valley and, as always, may you have a very fruitful new year! Sincerely, Teresa Nees Mesa County Noxious Weed & Pest Management

2 Upper Grand Valley Pest Control District Newsletter BobHammon, CSU Tri-River Extension Etymologist New Pest Alert Grape Phylloxera Found In Mesa County Grape phylloxera, Daktulosphaira vitifoliae, is one of the most destructive pests of vineyards worldwide. Grape phylloxera is native to the northeastern US. Many native North American grape species are resistant to phylloxera feeding but European species, especially cultivars of Vitis vinifera are susceptible to their feeding. Therein lays much of the problem; these are the most desirable varieties for quality wine production. Phylloxera was discovered in France in 1868, and it necessitated the destruction of more than 1 million hectares of vineyards and replanting on resistant rootstocks. Since then, it has spread to almost every major viticultural region of the world. Western Colorado was thought to be phylloxera free until it was discovered at several sites in Mesa County in November and December Grape phylloxera is a tiny aphid-like insect with a complex life cycle. There are two feeding forms of the aphid, one that feeds on roots and another that feeds above ground on leaves. The aerial form makes small reddish galls on developing leaves. These galls can be highly visible but are not typically damaging to the plant vigor or yield. The root feeding form is difficult to diagnose when in low population levels. Once the aphids have reached a high enough population to show symptoms in an affected area, the vineyard is doomed. Symptoms are a decline in plant vigor, early maturity, galling and distortion of root growth over an area that usually starts in a spot and expands as the aphids move to adjacent plants. There is no way to eradicate the insect and it will eventually kill susceptible grape vines. The only way to manage a phylloxera infestation in the long term is to replant the vineyard on resistant rootstocks. Phylloxera behavior can vary depending the variety of grape, climate, and soil type. Root feeding forms can live on, but not damage resistant varieties. Page 2 Above: Grape phylloxera on a root. Upper right: Magnified image of a single phylloxera inside the Q on a quarter. These symptomless plants can harbor aphids that infest surrounding susceptible types. Vinifera type varieties vary greatly in their susceptibility. Almost all infested areas have had to move to growing susceptible vinifera grape varieties grafted on to resistant rootstocks. Virtually all vinifera grapes grown in western Colorado are self-rooted. In the long term view, all will have to be replanted to resistant rootstocks if grape phylloxera follows the same infestation pattern it has followed in most other situations. Plant materials that are brought into the area from out of It is in the best interest of any western Colorado grape grower to prevent vineyards from becoming infested. state nurseries must be phylloxera free. Hot water treatments are effective in eliminating phylloxera from bare root plants, but the procedure must be special ordered from most nurseries. At the very least, plants should be inspected for the presence of aphids before they are planted. Magnification is necessary to properly identify these microscopic insects. Transfer of phylloxera between vineyards within the area occurs when the mobile stage known as crawlers move on people, machinery, harvest bins, wind or other means. Growers have control over human mediated movement and are going to have to adapt their mindset to limit movement between vineyards that could bring in an infestation. Other areas that have been invaded with phylloxera have survived, but it has taken a change in the way growers manage their vineyards. There is no reason to suspect that western Colorado vineyards will be any different.

3 January 2017 The Cytospora Working Group was established in 2015 by CSU under the direction of Dr. Ioannis Minas and Dr. Jane Stewart, assistant professor of plant pathology of the Dept. of Bioagricultural Sciences & Pest Management. The Working Group is supported by the Western Colorado Horticultural Society with the objective to provide peach growers in western Colorado disease management solutions for controlling Cytospora canker. Local growers are invited to join the Working Group to help guide ongoing efforts by CSU researchers Cytospora Canker Studies at CSU s Western Colorado Research Center and extension agents working on effective control of this diease. An update on the most recent findings of CSU s Cytospora research will be given at the 2017 WCHS annual meeting in January in Grand Junction. The next meeting of the Cytospora Working Group is scheduled for the spring of Bob Hammon, CSU Tri-River Extension Entomologist Cytospora canker, or gummosis, on a local fruit tree Cane Fruit Pest Established in District Spotted wing drosophila, Drosophila suzukii, (SWD) was first found in North America in 2008 and has quickly spread to almost all fruit growing areas of the continent. It is primarily a pest of cane fruits, strawberries, blueberries, and cherries but has caused problems in grapes and other stone fruits. Its presence has brought challenges to growing a once relatively easy fruit, like raspberries. This small fruit fly differs from our familiar fruit flies in that it lays eggs in perfectly sound fruits as they ripen, and the tiny maggot-like larvae cause them to prematurely soften and rot. Their appearance within days of harvest makes control difficult. It can also act more like a conventional fruit fly and reproduce in over-mature and damaged apples, pears, peaches, melons and possibly tomatoes. Spotted wing drosophila, male The Upper Grand Valley Pest Control District has helped support a SWD monitoring program for the past four years to keep track of SWD in susceptible fruits within the District boundaries. This trapping has detected adult SWD primarily in the late season raspberries and blackberries. They were found in one Palisade area cherry orchard in late June and early July in 2016, but populations did not reach damaging levels during the later growing season. To this point, SWD populations have been low in the upper Grand Valley, but they have been found in damaging numbers in Colorado front range cane fruits. Growers of susceptible fruits need to be aware of this potentially damaging pest because some year, when conditions are right for population development, it will become a damaging pest on someone s farm. Find more information at: spottedwing.org Page 3

4 Upper Grand Valley Pest Control District Newsletter Japanese Beetle Quarantine Protecting Colorado Agriculture & Nurseries in 2017 & Beyond Laura Pottorff, Nursery and Plant Pest Quarantine Program Manager, Colorado Department of Agriculture Japanese Beetle, Popillia japonica, is an invasive insect pest that was first introduced to the eastern United States in the early 1900s. Over time the insect has spread to infest all temperate regions of North America up to the 100th meridian. Prior to 1990, Colorado was thought to be protected from Japanese beetle colonization and establishment due to our semi-arid climate. Japanese beetle Larvae and eggs of Japanese beetle need at least 10 inches of soil moisture to thrive. Without supplemental irrigation, Colorado s environment would not be conducive to Japanese beetle survival. However, irrigation does occur to support many of our agricultural crops and urban landscapes, thereby making the pest a risk to certain areas of the state. The pest will move long distances on nursery stock. Nursery stock is defined as a perennial or woody plant such as grapes, trees, shrubs and other plants surviving year after year in agriculture production and landscapes. Due to transport of the pest on nursery stock from the east and mid-west, Japanese beetle has become established sporadically along the Front Range from Pueblo to Fort Collins. An additional population of the invasive pest that became established in Palisade, CO was eradicated as of 2011 due to the hard work and dedication of the Upper Grand Valley Pest Control District. Japanese beetle has a very wide host range and is difficult to control. Plants including Prunus and Malus species, grapes, turfgrass, lindens and many hundreds of other hosts will suffer severe damage. Management of Japanese beetle relies heavily on insecticide use, changes to the types of plants we use in our yards and to the way we irrigate our landscapes. A quarantine on nursery stock imported from Japanese beetle infested states, adopted at the request of the Colorado Nursery and Greenhouse Association (CNGA) in 2010, helps to slow the progression of the insect and prevent new Colorado introductions. Nursery stock may only enter Colorado if treated with certain insecticides or certified to be Japanese beetle free. Recently the Colorado Department of Agriculture proposed to expand our State s quarantine to include the Colorado counties of Pueblo, El Paso, Douglas, Arapahoe, Jefferson, Denver, Boulder, Broomfield, Adams, Weld and Larimer to prevent spread of the pest from known infested areas in Front Range to locations in eastern Colorado and the West Slope. Adopted by the Agriculture Commission and effective December 30, 2016, nurseries and landscape contractors in Front Range counties will need to make sure plant material that is grown or held within the Front Range is certified Japanese beetle free before transporting to other areas of the state. According to Allison Gault, CNGA Executive Director, The Colorado Nursery & Greenhouse Association (CNGA) is in support of the Japanese Beetle Quarantine as an effort to control the pest and attempt to keep it from leaving the quarantined counties. We recognize the impact it would have on uninfested counties as well as on the Fruit & Wine industries in the Western Slope communities and are willing to assist in slowing the spread. While the quarantine is a necessary next step, nurseries, sod farms and agricultural producers of fruit trees and wine grapes on the Western Slope should not be complacent. Help protect yourself and your industry by making sure the nursery stock you bring in meets Colorado s Japanese Beetle Quarantine. All nursery stock from the eastern and midwestern U.S. and the 11 Colorado counties under quarantine will have certification documents that accompany the stock. These documents describe how that stock meets Colorado s quarantine. Check with the nurseries you order from to make sure they meet our quarantine, before you order. CDA inspectors will be making a special effort to educate everyone impacted and answer questions during the 2017 inspection season. Enforcement of the new quarantine provisions will begin in Page 4

5 January 2017 Typical JB trap and lure. Local Japanese Beetle Update The summer of 2017 will mark the 13 th year that the Colorado Department of Agriculture Insectary, CSU Tri River Area Extension, Upper Grand Valley Pest Control District, Mesa County & Town of Palisade have been working together with Mesa County residents to monitor and control Japanese beetle in Palisade, CO. Although JB has been absent from the area for several years, efforts toward eradication of any new population transported from the Front Range or elsewhere will continue due to the great threat that JB poses toward not only our fruit industry, but our turf and other ornamental plants as well. Japanese beetle monitoring typically begins by early June and lasts through September, corresponding with the peak flight time of the insect. Town of Palisade residents are contacted and asked to voluntarily allow a plastic trap to be placed on their property near host plants such as Virginia creeper and rose bushes. Usually traps are set in the area of the original JB infestation, and easily mapped with a GPS app. Traps are set with a pheromone lure as well as a floral compound and checked and changed twice during the season. No Japanese beetles have been identified in the UGVPCD or the county since With continued efforts we hope to keep Mesa County JB free! Palisade Insectary: A Weed & Pest Control Resource Dan Bean, Insectary Director The Palisade Insectary was founded in 1945 in response to the newly introduced Oriental fruit moth, Grapholita molesta (family Tortricidae). In the beginning the sole mission of the Palisade Insectary was to rear and release the parasitoid wasp Macrocentrus ancylivorus (family Braconidae) to control Oriental fruit moth (OFM) which is a major pest of peaches. The Insectary modified rearing methods developed in California in the 1930 s, enabling the production of up 3.5 million M. ancylivorus (known as Mac) pupae per year. The program has been successful and, with resources provided by the Colorado Department of Agriculture and the Town of Palisade, continues to provide the parasitoid wasp for OFM control in peach orchards. Mac wasps don t overwinter in the upper Grand Valley and so need to be released every season for the control of OFM. Wasp pupae are produced at the Insectary and distributed in paper Page 5 bags to peach farmers in the Valley. Each bag holds 1,000 pupae which will emerge as adults after they are hung in peach orchards, and will provide enough adult wasps to control OFM over 1 acre of peaches. An adult female wasp can locate and lay an egg in an OFM larva resulting in death as the larva is consumed from the inside by the developing immature wasp. The Insectary also monitors for the presence of OFM in the Upper Grand Valley using pheromone baited sticky traps. This year, for instance, we picked up a season total of 51 OFM adults from 13 trapping stations around the Valley. Such a low number indicates that Oriental fruit moth is being controlled in the Valley. In addition to OFM control the Insectary currently has a number of other projects focused primarily on weed biological control. Knapweed Weevil Larinus minutus Our weed biocontrol targets include tamarisk, diffuse knapweed, spotted knapweed, puncture vine, Dalmatian toadflax, yellow toadflax, Russian knapweed, musk thistle, field bindweed and Canada thistle. These weeds originated in Eurasia and North Africa and were introduced without natural enemies. The goal of all of our weed biocontrol projects is to introduce host specific biocontrol agents that are found with the invasive weeds in their native ranges. We also monitor the progress of biological control in weed suppression and have monitoring programs covering several of our target weeds. In addition to our current weed control projects we are hopeful that new agents will become available for houndstongue, hoary cress and Russian olive. These weeds are biocontrol targets and now have some promising agents in the testing and development stages in overseas labs. Page 5

6 Upper Grand Valley Pest Control District Newsletter Is Plum Curculio Present in Mesa County? Bob Hammon, CSU Tri-River Extension Entomologist A Grand Junction Redlands area resident brought a sample of insect-damaged plums from a backyard tree this summer. There were exit holes and egg laying scars on the skin of the plums, and when opened, a small weevil larva was present. Plum curculio larvae (right) are whitish, about 1/3 inch long when fully grown, with a distinct brown head capsule and no legs. Adult beetle is shown on the left. The larva had eaten its way from the surface of the plum to the pit, but not damaged the pit. The insect is suspected to be plum curculio, but efforts to collect adults for positive identification were unsuccessful in Plum curculio, Conotrachelus nenuphar, is a major pest of stone and pome fruits across much of the world. It is not recorded from western Colorado, but is present in Utah orchards along the northern Wasatch Front. There are some quarantine restrictions on interstate movement of tree fruit from infested areas, most notably a restriction on Colorado peaches moving into Arizona. Plum curculio is a small, rough snout beetle with mottled black, brown and gray coloration. They are about ½ inch long. The adult weevils overwinter in soil then move to trees in the spring. Movement to trees can take an extended amount of time, but mostly occurs within two weeks of petal fall. Female weevils cut a distinctive crescent shaped flap in the skin of the fruit and lay eggs under the skin. When eggs hatch the legless, whitish grub burrows into the flesh of the fruit. When the larvae are done feeding, they leave the fruit through clean exit holes. No frass or webbing will be evident, in contrast to codling moth damaged fruit, which will have frass at the exit hole. It is important for the western Colorado fruit industry to know if plum curculio is present in the area so growers are prepared if it does make any appearance in local orchards. If you suspect plum curculio presence in your back yard fruit trees or orchard, please contact Tri River Area Extension for diagnosis. Get Involved With the Western Slope Cytospora Working Group Western Colorado has a long, rich tradition of growing fruit trees dating back to the early 1880 s. Four Western Colorado counties (Mesa, Delta, Montrose, Montezuma) account for 87% of Colorado s fruit tree acreage. The Grand Valley is the top production area for peaches, the major tree fruit species grown in Colorado. Peach production in Colorado in 2014 was 12,650 tons, valued at $30,705,000 (Colorado Agricultural Statistics, 2015). Total annual losses caused by Cytospora canker on stone fruit can average 15-20% depending on the area, management practices and cultivars. In a Colorado State University survey of 200 orchard-acres conducted in March and April of 2015, 100% of the orchards surveyed throughout the Grand Valley, North Fork of the Gunnison River region and as far south as Olathe were infected with Cytospora spp. At the newly established Cytospora Working Group meeting, growers, CSU Researchers and Extension agents and Western Colorado Horticultural Society board members discuss potential measures needed to combat this disease. Page 6

7 January 2017 Susan Carter; Your Local Horticulture Resource Susan started with CSU Extension in February 2014 and was the Master Gardener Program Coordinator for a year before being hired as Extension Horticulture Agent for the Tri River Area encompassing Mesa, Delta, Montrose & Ouray counties. Susan has worked with plants all her adult life. She has been a production coordinator, nursery manager and landscaper. She used to grow potted fruit trees for a nursery and has a few fruit trees of her own. She has a bachelor s degree in Ornamental Horticulture and a master s in Landscape Architecture with a minor in Horticulture. Her position is 75 % commercial horticulture, so she is working with vegetable and fruit growers, nurseries, greenhouses and landscapers. She is on the Cytospora Working Group for peaches and is a member of the Colorado Vegetable and Fruit Growers Association. She can help new growers get started on the right foot and can help solve growing issues with plants. She and John Rizza are working on coordinating a Beginner Orchard Class. Please contact her if you or someone you know would be interested in taking this class. Susan Carter (970) susan.carter@colostate.edu Susan will be in attendance at several upcoming conferences and events and would love for you to stop by and say hello! Welcome, Dr. Ioannis Minas! Dr. Ioannis Minas (970) ext.205 ioannis.minas@colostate.edu Colorado State University in the fall of 2015 appointed Dr. Ioannis Minas to lead the research, outreach and extension education programs to support the Colorado tree fruit industry. Dr. Minas received his doctorate in pomology and postharvest physiology from Aristotle University of Thessaloniki, Greece. During his doctoral studies, he was appointed a junior specialist in the Plant Sciences Department at University of California Davis. He currently holds the post of assistant professor of pomology at CSU s Department of Horticulture & Landscape Architecture located at the Western Colorado Research Center at Orchard Mesa, Grand Junction, CO. Pomology, a Latin word meaning the study of fruit, is the applied life science of perennial temperate, subtropical and tropical fruit cultivation and production. The CSU pomology program under his direction focuses in orchard systems management to maximize productivity and fruit quality, rootstocks and cultivars evaluation, cold damage avoidance and mitigation, and postharvest physiology of peaches, apples and sweet cherries. Palisade Insectary /10 Road Palisade, CO (970) dan.bean@state.co.us Western Colorado Research Center 3168 B 1/2 Road Grand Junction, CO (970) Tri River Area Extension Grand Junction Office 2775 US Highway 50 (970) Page 7

8 Upper Grand Valley Pest Control District PO Box 20,000 Department 5087 Grand Junction, CO Regulated Species Insects: CODLING MOTH (Laspeyresia pomonella) (CROWN BORER) (Synathadon rugilosus) JAPANESE BEETLE (Popillia japonica) ORIENTAL FRUIT MOTH (Grapholita molesta) PEACH TWIG BORER (Anarsia lineatella) PEAR PSYLLA (Psylla pyricola) SAN JOSE SCALE (Aspidiotus lineatella) SHOT HOLE BORER (Scolytus rugulosus) CANADA THISTLE (Cirsium arvense) WHITETOP (Cardaria draba) LEAFY SPURGE (Euphorbia esula) DALMATION TOADFLAX (Linaria dalmatica) YELLOW TOADFLAX (Linaria vugaris) GREATER PEACH TREE BORER WESTERN CHERRY FRUIT FLY (Rhagoletis indifferens) WEEDS: RUSSIAN KNAPWEED (Acroptilon [Centaurea] repens) The mission of the Upper Grand Valley Pest Control District is to protect the commercial fruit industry from insect, disease and weed infestations arising from within the district boundaries The UVGPCD was formed in 1965 under Colorado Revised Statutes Title 35, Article 5, Pest Control Districts.