9:00 a.m. Applying Pesticides On-Target: Common Sense and Technology. Mary Hausbeck, Plant Pathology Dept., MSU

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1 Great Lakes Fruit, Vegetable & Farm Market EXPO December 4-6, 2007 DeVo Place Convention Center, Grand Rapids, MI Asparagus Tuesday morning 9:00 am Where: Grand Gallery (lower level) Room C Recertification credits: 1 (1B, PRIV CORE) CCA Credits: PM(1.5) CM(0.5) Moderator: Norm Myers, Oceana Co. MSU Extension, Hart, MI 9:00 a.m. Applying Pesticides On-Target: Common Sense and Technology Andrew Landers, Pesticide Application Technology Specialist, Cornell Univ. 9:45 a.m. Asparagus Disease Update Mary Hausbeck, Plant Pathology Dept., MSU 10:20 a.m. Horticultural Strategies for Improving Asparagus Production in a Replant Situation Mathieu Ngouajio, Horticulture Dept., MSU Buck Counts, Plant Pathology and Horticulture Dept., MSU 10:45 a.m. Is There a Future for Me in the Asparagus Business? John Bakker, Michigan Asparagus Advisory Board, Dewitt, MI

2 Applying Pesticides On-Target: Commonsense and Technology Andrew Landers Cornell University, Barton Laboratory, Geneva, NY Introduction There are many news developments in spray technology that will help reduce the costs involved in applying pesticides. The main costs associated with pesticide application are the costs of the pesticides, which continue to rise in many cases. Any technology that reduces the amount of product necessary to control a weed, insect or disease, or improves its effectiveness, is welcome. Commonsense and technology is required to improve spray deposition onto sweet corn plants. Droplets Poor spray coverage is a major factor contributing to poor insect control. Better coverage leads to better control, and a thorough application of an effective material is required. The results of uneven coverage frequently increases the number of sprays required and therefore increases the amount of pesticide that must be applied. Whilst canopy size will affect application volume, there are equal dangers in not applying enough spray and also in applying too much. There is an optimum quantity required for a thorough coverage of the target. The old adage that you should spray until the leaves drip is misplaced; likewise lowering spray rates to below the minimum which offers control is also misguided advice. A number of growers have reduced application volumes to extremely low levels and are observing poor insect control due to inadequate coverage. Interestingly, research around the world confirms similar results and also indicates that there is an optimum volume to provide thorough coverage and pest control. Droplet size Physics is a wonderful subject! A droplet with twice the diameter of another has four times the area and eight times the volume. Eight smaller droplets having the same total volume as the larger droplet will provide twice the coverage of the larger droplet. Conversely, for the same volume of liquid, when you halve the diameter of a droplet you increase the number of droplets eight-fold. For instance, when a single 200 micron droplet is halved to 100 microns, you disperse its liquid into eight of these smaller droplets. Halve them again to 50 microns and you now get 64 droplets etc. Similarly the area covered increases as the size of droplets decreases, assuming the volume stays the same. As described above, a 200 micron droplet has 64 times the volume of a 50 micron droplet. Assuming the target area covered by a droplet is equal to its cross sectional area, 64 droplets of 50 microns will cover four times the area of a single 200 micron droplet, even though both scenarios involve the same amount of spray.

3 A combination of the optimum volume and droplets that adhere to the leaves will provide good insect and disease control. It must be stressed that too fine a droplet will result in off-target drift and equally important, especially in hot weather, lead to evapouration of droplets. Even modest winds, (v>7 mph) can result in high levels of drift. Conversely, the total absence of wind (v<1 mph) can be a significant risk factor, especially in temperature inversion conditions that typically occur on very hot days. A spray cloud may remain airborne under such conditions and when air currents appear, spray may be deposited some distance from the intended target. A nozzle s droplet size spectrum determines deposition and drift. Conventional flat fan nozzles fitted to a crop sprayer produce droplets in the range of microns. There are 25,000 microns in one inch. Drift is a major problem with droplets less than 100 microns. Increasing the Volume Median Diameter (VMD) will certainly reduce drift, but too large a droplet will bounce off the leaves to the ground, thus causing pollution, wasting money and resulting in less product on the target. Drift has been a major concern for some years, off target application wastes money, reduces deposition on the target plant, pollutes water courses and may cause nausea to other people. New nozzle selection technique A number of pesticide manufacturers are adopting the ASABE/BCPC nozzle selection system and stating on the pesticide label the spray classification needed for their product. Reference nozzles, tested in a laboratory using a laser analyser, are then classified according to the characteristics of the spray produced. Very fine, fine, medium, coarse and very coarse are the categories of spray. The label recommendation makes nozzle selection far easier for the sprayer operator. A general guideline is: Fine classification for fungicides and insecticides Medium classification for herbicides Coarse classification for pre-emergent sprays However, weather conditions, particularly wind and its effect upon drift, must be taken into consideration. If the label or supplier makes no recommendation concerning nozzles or spray quality, then a reasoned choice of spray quality must be made, based upon the target, the product and the risk of drift Small droplets, less than 100 microns, drift in the air, whereas larger droplets, over 300 microns tend to bounce off leaves. A number of nozzle manufacturers offer low-drift nozzles to reduce drift. Correct nozzle selection is one of the most important yet inexpensive aspects of pesticide application. The target Asparagus ferns provide an excellent if in-penetrable target. A fine leaf and stalk provide for excellent droplet capture similar fine structures are often used in spray drift measurement trials where, for example, pipe cleaners are used to provide a fine surface to collect very small droplets. Whilst this structure is good at collecting fine droplets, it can also be its downfall. Droplets are required not only to be the correct size to adhere to the fine leaflets but also enough mass to penetrate throughout the canopy. Too fine a droplet, ideal for adhering to the ferns, results in not enough penetration unless high pressure is used this often leads to drift. Too large a droplet will bounce off the leaves and pass straight down to the ground. A compromise is required, fine to medium size droplets are the best for this task. Growers should select the correct nozzle based upon application rate per acre from the nozzle catalogs, then refer to the spray quality classification tables to check that the nozzles produce a fine/medium spray quality.

4 As penetration into the canopy is critical, researchers have developed methods of improving boom design and nozzle type. In Germany, for example, large areas of asparagus are grown and researchers prefer the basic boom design as shown in figures 1 and 2. Directing individual nozzles to provide better penetration is crucial and in both cases the flow rate is matched to the growing canopy. Note in figure 1, the Agrotop method uses the nozzles angled forwards by 15 o. In figure 2, by Norbert Laun of DLR, Rheinpfalz, note the use of the Lechler IDK nozzles or off-centre tips fitted at the top and bottom of the booms, these nozzle tips reduce drift above the crop and losses to the soil. In both cases they are using TD/AVI air induction nozzles, either standard or compact from Lechler or Agrotop.

5 TD/AVI towards ground Hose diameter ½ Nozzle angle 15 to the front in 63 in TD/AVI towards ground in TD/AVI pointing upwards TD/AVI pointing upwards TD/AVI-OC in in in Young Plants Normal Plants Dense Plants 6.56 ft 64 gal/acre speed 2.8 mph at 87 psi = 2.37 gal/min 86 gal/acre speed 2.8 mph at 145 psi = 3.17 gal/min 107 gal/acre speed 2.5 mph at 189 psi = 3.51 gal/min Figure 1 The Agrotop system Application for two complete rows or 3 rows in in Nozzle to limit drift in in 9.84 in 7.87 in 5.9 in 5.9 in Distance from ground in Figure 2 The Kahlsruhe system by Norbert Laun, DLR, Rheinpfalz

6 Asparagus Disease Update Dr. Mary K. Hausbeck ( ), J.W. Counts, and B.D. Cortright Michigan State University, Department of Plant Pathology In Michigan, commercial asparagus production begins with seeds planted in nursery fields in early spring. Plants are grown until the following spring, when the young crowns are harvested, and then transplanted into production fields. Fusarium disease, caused by the fungi Fusarium oxysporum f.sp. asparagi and F. proliferatum, can kill seedlings in crown nurseries, plants in young asparagus fields, and cause a slow decline in productivity of mature fields. Losses due to Fusarium disease can be staggering because declining fields are abandoned early and years of productivity are lost. Currently, no fungicides are effective against Fusarium spp., cultural strategies (such as adding sodium chloride to the soil) have not helped, and breeding for genetic resistance to this disease has been unsuccessful. In 2004, disease symptoms caused by another soilborne fungus, Phytophthora sp., were noted in the experimental trials and grower fields after heavy rains. Investigation into this disease revealed that Phytophthora sp. is much more prevalent in the soils of the asparagus-growing region and more of a threat to asparagus production than previously thought. The following objectives were proposed: (1) Evaluate the distribution of Fusarium spp. at different soil depths and the effectiveness of fumigants and crown soaks on Fusarium crown and root rot; (2) Evaluate preplant crown soaks for control of Fusarium and Phytophthora diseases; (3) Maintain and record data from established drip irrigation beds evaluating the effect of irrigation and drip-applied chemical and biological treatments on Fusarium and Phytophthora diseases. Table 1. Products tested in asparagus field trials. Product Active ingredient Labeled Cannonball 50WP... fludioxonil no K-Pam... metam potassium yes Presidio 4FL... fluopicolide no Ridomil Gold 4EC... mefenoxam yes Scholar 50WP... fludioxonil no Telone C ,3-dichloropropene/chloropicrin yes Topsin 70WSB... thiophanate-methyl yes Evaluation of fumigants and crown soaks for control of Fusarium crown and root rot of asparagus In the fall of 2005 a trial was established on a grower cooperator s farm in Oceana County, MI in a field with a history of asparagus production. Fumigant treatments consisted of K-Pam 60 gal/a, Telone C gal/a (Table 1), and an untreated control and were replicated four times in a randomized complete block design. Fumigants were shank applied on 7 Oct 2005 to a depth of in. in beds that were 13 ft wide by 80 ft long. Treatments were separated by a fumigated (Chloropicrin 100%) raised black-plastic-mulch-covered bed. Beds were seeded on 5 May 2006 using disinfested Millennium

7 asparagus seed in three rows 18 in apart in the center of the bed with a seed depth and a spacing of 2 in. After fumigation (21 Oct 2005) soil samples were taken from 5 points in the center of the beds to a depth of 30 in. using a JMC soil probe with a plastic liner to maintain the soil profile. Samples were divided into 6-in. increments and allowed to dry for 7 days. After drying soils were diluted in 0.05% water agar solution and then plated onto PPA or Komada s selective media. Plates were incubated for 7 days and resulting Fusarium colony-forming units (CFUs) were counted and identified. In Apr 2007, crowns were dug, rated and weighed. CFUs were significantly higher for the untreated control plot compared to both fumigant treatments (Table 2). At the soil depth of 0-6", the Telone C-35 treatment had the fewest CFUs. Overall, the CFUs were lowest at the 6-12" level. When assessed in Oct 2006, the number of seedlings in each treatment plot did not differ significantly among treatments. In Apr 2007, the number of crowns that were scored favorably for low Fusarium infection (#1 = 0-1 Fusarium lesions per crown) were significantly higher for the fumigant treatments of K-Pam and Telone C-35 than for the untreated. There were significantly more unusable crowns from the untreated control than from the fumigated treatments. Although the crowns from the Telone C-35 treatment had the greatest mass as exhibited by fresh weight, they were not significantly different from the untreated control. Table 2. Fumigants and crown soaks for Fusarium crown and root rot. CFUs z of Fusarium spp. after fumigation Crown rating y (%) Apr 2007 Seedlings Soil depth (in.) Oct 2006 Unusable Treatment and rate/a (plants/50 ft) #1 x #2 x #3 x (#2,#3) Weight (lb) Untreated... 18,450 b 4,600 b b w 37.6 b 44.7 b 82.3 b 5.8 K-Pam 60 gal... 1,510 a 70 a a 10.5 a 4.0 a 14.4 a 6.9 Telone C gal a 200 a a 3.9 a 0.8 a 4.7 a 10.3 z CFU = colony-forming units. Column means for CFUs with a letter in common are not significantly different (Tukey s test; P=0.05). y Crowns rated as follows: #1=0-1 lesions per crown, #2=2-5 lesions, 3=>5 lesions. x Percentage of crowns that were determined to meet the classification requirement. w Column means with a letter in common or with no letter are not significantly different (Fisher LSD Method; P=0.05). Evaluation of preplant crown soak treatments for control of Fusarium crown and root rot and Phytophthora spear and root rot This experiment was conducted in a commercial field in Oceana County near the city of Hart, MI. The field has a history of several asparagus production plantings that suffered severe decline caused by Fusarium and Phytophthora. The soil at the site was a fine sandy loam and was previously planted to asparagus. Treatment plots were arranged in a randomized complete block design. Rows for the experiment were plowed by a single bottom plow to a depth of 12 in. and were spaced 5 ft apart. Treatment rows were 20 ft long and crown spacing in the row was 7.5 in. (27 crowns per row). Before planting, Jersey Knight one-year old crowns were treated by soaking in a chemical solution for 10 min. Immediately after soaking, the crowns were planted in a single line on 17 May. Foliar diseases were controlled with applications of Bravo Weather Stik (2 pt/a) every 14 days starting on 15 Jun. Stand counts for the entire treatment rows were taken and each live fern was measured for height. Data were analyzed using Sigma Stat version 3.1 (Systat Software Inc.) and treatments were compared using the Fisher LSD multiple comparison test. Average monthly minimum and maximum air temperatures ( F) were: May (47.1and 71.8); Jun (53.7 and 79.7); Jul (57.4 and 79.2); and Aug (58.3 and 79.0). Rainfall totals (in.) were 2.2, 1.2, 2.1, and 2.5 for the same respective months.

8 Fern emergence was similar for all treatments at the Jun rating, and stand counts did not differ significantly (Table 3). In Sep, treatments were not statistically different, but the untreated control had the lowest stand count and treatments with Ridomil Gold EC alone or in combination with Cannonball 50WP had the highest stand counts. In Jun there was a noticeable increase in height with treatments treated with Ridomil Gold EC or Presidio 4FL, but these differences were not significant. This height difference was not as noticeable in Sep as significant deer feeding damage occurred across the plot. Table 3. Preplant crown soaks for Fusarium and Phytophthora diseases. Treatment and rate/100 gal Stand count Height (in.) Jun Sep Per acre Jun Sep Untreated 34.5 * , Cannonball 50WP 0.5 oz , Topsin M 1 lb , Ridomil Gold 4EC 1 fl oz , Presidio 4FL 4 fl oz , Cannonball 50WP 0.5 oz + Ridomil Gold 4EC 1 fl oz , Topsin M 1 lb + Ridomil Gold 4EC 1 fl oz , Cannonball 50WP 1 oz + Ridomil Gold 4EC 1 fl oz , * There were no significant differences among treatments (Fisher LSD Method; P=0.05). Effect of irrigation and drip-applied chemical and biological treatments on Fusarium crown and root rot and Phytophthora spear and crown rot The plot was established in 2003 under dry conditions, which favored Fusarium development. In 2004, Phytophthora symptoms, including water-soaking and shriveling of spears, were noticed during harvest, possibly enhanced by heavy rains during May. Weather conditions were dry and cool during Jul and Aug In 2005, hot dry conditions were normal for the growing season. Weather conditions in the 2006 growing season were approximately normal. However, there were several severe weather events late in the season limiting the number of ratings. In 2007 temperatures were approximately normal with below normal precipitation. Table 4. Average total fern when asparagus was treated with mefenoxam or with drip treatments. Total Fern Treatment and rate Drip treatment amendment Untreated * a No mefenoxam a Mefenoxam 4 pt/a b Drip applied treatments Untreated ab Irrigated a Nonpathogenic Fusarium 2.6 gal/1000 row ft ab Topsin 70WSB 0.5 lb/a b Scholar 50WP 8 oz/100 gal b * Treatments with the same letter or with no letter are not significantly different (P>.05, Tukey-Kramer). At the end of this multi-year study, differences among the treatments were not observed (Table 4). Although applications of mefenoxam appeared to be helpful to the health and total stand counts in 2005, the positive effect was not long lasting.

9 This research was funded by the Ontario Asparagus Growers Marketing Board/Canada-Ontario Research and Development Program (Agriculture and Agri-Food Canada and the Ontario Ministry of Agriculture, Food and Rural Affairs), MSU MAES Project GR06-083D, and Michigan Asparagus Research, Inc.

10 Horticultural Strategies for Improving Asparagus Production in a Replant Situation Dr. M. Ngouajio 1, Dr. M.K. Hausbeck 2 and J. Counts 1, 2 1 Department of Horticulture 2 Department of Plant Pathology Michigan State University Introduction and rationale Asparagus replant suppression is a major threat to asparagus production worldwide. The problem is more pronounced in areas with a long tradition of asparagus production where virgin land is limited. Under those conditions early decline and stand reduction are observed in newly replanted fields and the life span of the fields can easily be reduced to 5-10 from years as they are abandoned prematurely. Fungicides and soil fumigants are use to help reduce the impact of the problem. If proven effective, disease free planting materials like greenhouse-grown transplants and crop management practices that help improve soil quality could potentially be added in the tool box for management this scourge. Objective The overall goal of this work is to test effects of alternative planting methods and soil amendments on asparagus replant suppression. Specific objectives were 1) Determine optimum plug cell size for transplant production in the greenhouse, 2) compare the performance of transplants with crowns under field conditions, and 3) test the effect of soil amendment in a replant situation. STUDY I. Effect of plug cell size on transplant growth Methodology The trial was conducted in the Michigan State University research greenhouses. Nine transplant trays with various cell shapes and number (38 to 200 cells) were used in a completely randomized design. Trays were filled with Bacto potting mix and seeds (Millennium) were planted 0.5 inch deep in the center of a cell on 3 Oct. Seedlings emerged 14 days after planting on 17 Oct. Foliar fertilizer ( ; MoraLeaf) was first applied at 50 ppm on 28 Oct (11 days after emergence) and fertilized daily after that. Fertilizer rate was increased to 75 ppm when plants became larger. Ratings were conducted every two weeks stating at 16 days after emergence (DAE). Ratings consisted of number of shoots, shoot fresh weight, shoot dry weight, root fresh weight, root dry weight, shoot length, and root length. Results Asparagus transplants are normally grown for 8-10 weeks in the greenhouse prior to being transplanted in production field. Therefore the 58 and 72 DAE (8 and 10 weeks) results are more relevant and are presented here. Asparagus root size is the most important factor that determines successful field establishment. The shoot is important during transplant production but the fern present at planting normally dies and the new fern is formed using reserves stored in the crown. Transplant weight increased as plug cell size increased. At both 8 and 10 weeks after emergence shoot and root weights were maximized with larger cells (38-cell flat) compared to smaller cells (200-cell flats). This observation was true for both fresh and dry weight (Table 1 and 2). Based on the 10 weeks data on transplant fresh and dry weights, flats with 72 or fewer cells should be recommended. Smaller cell size (flats with more cells) increase competition for light and

11 impose more restriction to root growth. Once the cell volume is filled with the root systems, further transplant size improvement is limited. Clearly the 200 cell flat (and 128 cells to some extend) should not be recommended for asparagus transplant production. Table 1. Average number of shoots per plant, average shoot and root fresh weight for each of the cell sizes and shapes at 58 DAE (8 weeks). Treatment Number of shoots Fresh weight (g/plant) Dry weight (g/plant) (#/plant) Shoot Root Shoot Root 38 deep 2.9 a * 1.56 a 1.67 a 0.30 a 0.22 a 38 shallow 2.9 a 1.53 a 1.41 b 0.26 ab 0.19 a ab 1.15 b 1.11 c 0.19 bcd 0.13 b 72 square 2.1 c 0.68 de 0.44 fg 0.12 e 0.08 cd 72 octagon 3.0 a 1.09 b 0.87 d 0.25 ab 0.18 a a 0.77 cd 0.60 ef 0.17 cde 0.12 b ab 0.89 c 0.81 de 0.21 bc 0.18 a ab 0.57 e 0.51 f 0.14 de 0.12 bc b 0.37 f 0.24 g 0.10 e 0.07 d * Treatments with the same letter are not significantly different at P=0.05(LSD). Table 2. Average number of shoots per plant, average shoot and root fresh weight for each of the cell sizes and shapes at 72 DAE (10 weeks). Treatment Number of shoots Fresh weight (g/plant) Dry weight (g/plant) (#/plant) Shoot Root Shoot Root 38 deep 4.3 a * 3.49 a 3.30 a 0.64 a 0.58 a 38 shallow 3.7 bc 2.11 b 2.15 b 0.31 b 0.27 bc de 1.52 c 1.71 bc 0.26 bc 0.23 bcd 72 square 3.3 de 1.33 cd 1.32 cd 0.19 cd 0.19 cd 72 octagon 3.7 bc 1.23 cde 1.94 b 0.25 bcd 0.33 b ab 1.05 def 1.05 de 0.19 cd 0.15 de cd 0.92 ef 1.08 d 0.18 cde 0.17 cde e 0.80 f 1.23 cd 0.17 de 0.24 bcd cd 0.32 g 0.47 e 0.09 e 0.08 e * Treatments with the same letter are not significantly different at P=0.05(LSD). STUDY II. Field comparison of transplant vs crown Methodology This study was established in summer 2006 on a cooperator s farm in Oceana County, MI, in a field with a history of asparagus production. Millennium and Jersey Knight asparagus seed were planted in 3 cell sizes (72, 98, 128 cells per flat) at a commercial greenhouse in Southeast MI. Seeds were planted 6 Apr and trays were then placed in a germination chamber. Trays were removed from the chamber after plants emerged (12 Apr). The transplants were maintained in the greenhouse for 8 weeks and then moved outside for 2 days prior to planting. Crowns were obtained from a commercial grower and were sorted for size. To reduce soil pathogen levels Sectagon 42 (75 gal/a) was applied on 10 May. Crowns were planted on 2 June and transplants were planted on 12 Jun in a 7 inch staggered rows with crowns being dipped in Topsin (20 oz/100 gal) for 10 min and planted directly into furrows. Insects were controlled with weekly applications of Sevin XLR Plus (3 pt/a) with Diazionon (1.5 pt/a) applied for asparagus miner control during the month of Aug. Foliar diseases were controlled with weekly applications of Bravo WeatherStik (3 pt/a). Foliar fertilizer ( ; MoraLeaf; 5 lb/a) was applied 3 times during the growing season of Stand counts were taken for number of shoots and number of dead shoots on 29 Sept 2006 and 25 Oct Shoot height was taken on 25 Oct 2007.

12 Results In 2006 all transplants, regardless of cell size and cultivar had significantly more shoots per plant then the standard one year old crowns in For Millennium the 72 cell plants and the 128 cell plants had significantly fewer dead shoots than the crowns in For Jersey Knight 128 cell plants had significantly fewer dead shoots than the 72 cell plants in In 2007, the 72 cell size of Millennium had significantly more shoots than the one year old crowns and all of the cell sizes for Jersey Knight had similar number of shoots. Plant stand was 97% with Jersey crowns and 100% with Millennium crowns and all transplants. Plants established from crowns were taller than those from transplants. The cell size did not seem to have major effects on transplant performance. Given the fact that the crowns were nearly one year older than the transplants, we can conclude that at this stage transplants have performed relatively well. However, it is premature to make a recommendation without yield data. Yield data will be conducted in Table 3. Number of shoots per plant and percent of dead shoots per plant for the 2006 and 2007 growing season. Treatment # shoots/ plant % Dead shoots Millennium Jersey Knight Millennium Jersey Knight Crowns x 4.0 b z 3.1 b 3.2 b 2.0 c 18.5 b ab - 72 cell trays y 6.5 a 3.7 a 4.6 a 2.0 c 8.3 a b - 98 cell trays 5.7 a 3.2 ab 4.9 a 2.3 c 9.3 a ab cell trays 5.5 a 3.6 ab 4.6 a 1.8 c 7.8 a a - x Plant spacing is 7.0 inches in a staggered row. y Plant spacing is 5.5 inches in a staggered row. z Treatments with the same letter are not significantly different at P=0.05(LSD). Table 4. The percent of stand for 20 feet of row based on the two planting densities and fern height for Millennium and Jersey Knight asparagus. Asparagus Stand Shoot height Treatment (% of initial density at planting) (inches) Millennium Jersey Knight Millennium Jersey Knight Crowns x a z a 72 cell trays y b cd 98 cell trays bc cd 128 cell trays b d x Plant spacing is 7.0 inches in a staggered row. y Plant spacing is 5.5 inches in a staggered row. z Treatments with the same letter are not significantly different at P=0.05(LSD). STUDY III. Effect of soil amendment Methodology The trial was established in commercial production fields in Oceana County, MI in the spring of Two fields in a replant situation were used following production practices for each grower cooperator. Field one used non-treated (cannonball) crowns planted in a non-fumigated seedbed. Field two used treated (cannonball) crowns planted in a fumigated seedbed. Treatments were set up in a randomized complete block design with four replications. Field one was planted on 23 May using Millennium crowns (about 77 g each). Rows were spaced 5 ft on center and crowns were spaced every 12 inches.

13 Field two was established on 6 June using Millennium asparagus crowns (about 60 g each). Double rows were spaced 5 ft on center and crowns were spaced every 7 inches in a staggered row. All treatments were applied at planting except for TerraClean which was applied on 6 June. Plot management was conducted by the growers following commercial production standards. Treatments included: 1) Dairy compost (10 t/acre); 2) Mustard bran (2 t/acre); 3) SoilBuilder (2 gal/acre after TerraClean at 2 gal/acre); 4) Frame + SoilLife + Crown Acre (Proprietary soil amendment combination not registered); 5) Control with treated crowns; 6) Control with untreated crowns Ratings were taken for fern health, fern height, plant stand, and shoots per 10 plants on 25 Oct for both trials. Due to a heavy cover crop only fern health and shoots per 10 plants were recorded for field two. Results There was no significant benefit for applying any of the soil amendments. Given the fact that asparagus was established from crowns and that most of the early growth is supported by the reserves in those crowns, this type of result was expected. This study will be monitored in 2008 to determine the potential effects of each amendment. Table 1. Effect of soil amendment on asparagus performance under a replant situation in nonfumigated beds. First season evaluation (about 5 months after treatment application). Treatment Fern evaluation Height Shoots per 10 Shoots per Plants per (scale of 0 to 10) (inches) plants plant 25 ft Untreated control Mustard bran Soil Builder Treated control Compost Frame LSD Fern evaluation is based on a scale of (0 poor to 10 excellent) Table 2. Effect of soil amendment on asparagus performance under a replant situation in fumigated beds. First season evaluation (about 5 months after treatment application). Treatment Fern evaluation Shoots per 10 plants Shoots per plant Treated control 9.5 a * Mustard bran 8.9 a TerraClean 7.5 b SoilBuilder 8.9 a Compost 8.9 a Frame 8.7 a LSD * Treatments with the same letter are not significantly different (P=0.05, LSD) Acknowledgments Funding for this work was provide in part by USDA NC-IPM, Project GREEEN (Generating Research and Extension to meet Economic and Environmental Needs), and Michigan Asparagus Research Committee. We appreciate in-kind and technical support from our grower cooperators (Tom Oomen, Rick Oomen, Ken Oomen and Ralph Oomen). Thanks to Norm Myers and John Bakker for their invaluable input.