Serving the research and extension needs
of Long Island's horticultural industries.

Contact:
3059 Sound Ave.
Riverhead, NY 11901
(631) 727-3595
(631) 727-3611 (fax)
Dr. Mark Bridgen, director
mpb27@cornell.edu

Organic Farming Research

Since 2000, the Long Island Organic Advisory Committee has met and research has been conducted at organic farms and at LIHREC.

There is a two-acre field at LIHREC exclusively for applied research in cultural practices and pest management within an organic production system and other organic research is conducted elsewhere at the center.

While most experiments have focused on one topic (e.g. pest management, fertility), our research team works together on overall production practices for experiments in the organic research field.

Projects include:

Evaluation of fertilizer for organically-grown tomatoes (LIHREC Organic field)

The four fertilizers treatments were: 1) No additional nitrogen (only Berseem Clover); 2) 1000 lbs/A North Country 5-3-4; 3) 625 lbs/A peanut meal 8-0-0; 4) 500 lbs/A fish meal 10-0-0, equivalent to 50 lbs/A of nitrogen in all treatments except #1. Treatments 1, 3 and 4 were supplemented with Rock Phosphate 0-3-0 (30 lbs/A P205) and Greensand 0-0-17 (40 lbs/A K20). Prior to the tomato crop, Berseem Clover was planted in spring 2003 and grown until killed during winter 2003-04. Amount of nitrogen from this rotational crop was not estimated. All fertilizer treatments were applied 4 days before transplanting in mid-June. Total yields of 'Red Sun' tomato were significantly higher with the 5-3-4 and fish meal treatments compared to the clover-only treatment. However, there were no significant differences in plant growth, marketable yield or fruit quality among the four treatments. This corresponded very well with the Pre-Sidedress Nitrate Tests that indicated there was greater than 25 ppm of NO3-N in the soil during the growing season. This critical value usually indicates adequate levels of nitrogen to produce a crop.

Nitrogen fertility and foliar disease management with compost tea and rescue treatments in organically-grown tomato (LIHREC Organic field)

'Red Sun' tomato seedlings were transplanted by hand in mulch of hairy vetch cover crop that was flail chopped 10 days earlier. A tractor equipped with a fluted coulter and an S-tine was used to cut 4-in. deep strips through the field for transplanting. Fish hydrolysate fertilizer (approx. 2.8 ml/plant of Organic Gem Liquid Fish 3-3-0.3 diluted in water 1:64) was placed in the opening before the seedling. Additional straw mulch was placed around plants to improve weed suppression. There was a trend toward higher yield for those plants that received peanut meal at 625 lb/A (equivalent to 50 lb/A of N) banded on 23 Jun to supplement the nitrogen provided by the vetch mulch and starter fertilizer, but yield did not vary significantly among treatments.

Powdery mildew, bacterial speck and Septoria leaf spot developed naturally. First symptoms were observed on 20 Aug. These diseases were not significantly less severe on plants sprayed 10 times with compost tea from 8 July to 8 Sept (see previous report). These diseases also were not controlled when the biofungicide Sonata was applied weekly from 11 Aug to 17 Sep immediately after compost tea was applied. Another group of plants sprayed with compost tea also received rescue sprays made after disease detection which were JMS Stylet oil applied twice for powdery mildew followed by 3 applications of the copper fungicide Champion for all 3 diseases. These plants appeared healthier than the others, but disease ratings did not differ significantly from other treatments.

An evaluation of the stale seedbed technique for leafy lettuce production (LIHREC Organic field)

A field study was conducted to examine two different types of seedbed preparation prior to direct seeding leaf lettuce 'Cabernet Sauvignon" as well as the need for post plant cultivation in stale seed bed culture. The beds were raised 17 days before the bed surface was cultivated with either shallow cultivating knives or floating tines with rolling baskets. The lettuce was planted the same day and either followed with a second cultivation or no postemergence cultivation.

The lettuce emerged 8 days after planting and was harvested 25 days after emergence. The results indicate that the best treatment in terms of yield was produced by the floating tines with rolling baskets and that post emergence cultivation did not increase yield or decrease weed growth significantly.

Evaluation of biopesticides for powdery mildew of pumpkin

The study focus was on 6 plant oil products because good control was achieved with a mineral oil, JMS Stylet-oil, in previous experiments conducted at LIHREC. A hydrogen dioxide product, OxiDate, was also tested. These 7 products fit the EPA biopesticide definition. Most are OMRI listed. Some are exempt from EPA registration. Sulfur (Microthiol Disperss) was included because it has performed well previously and is anticipated to be OMRI listed soon. All products tested provided some control of mildew on upper leaf surfaces applied weekly beginning after disease detection with a tractor-sprayer. GC-3 organic fungicide (30% cottonseed oil, 30% corn oil, 23% garlic extract), Organocide (5% sesame oil; 92% fish oil) and Eco E-Rase (97.5% jojoba oil) were as effective as Microthiol Disperss, JMS Stylet-oil, (organic formulation) and the conventional chemical fungicide Bravo Ultrex, providing 76-85% and 76-92% control on upper leaf surfaces, respectively, and 28-42% and 18-30% control on lower leaf surfaces. Other products tested were Bugitol (0.42% capsaicin and related Capsaicinoids), Sporan (17.6% rosemary oil; 82.4% wintergreen oil), and Trilogy (70% extract of neem oil).

Evaluation of compost tea and rescue treatments for powdery mildew applied to susceptible and resistant varieties of pumpkin

Compost tea was applied to foliage 9 times from 16 July, which was 3 weeks after transplanting and 10 days before powdery mildew was observed, through 8 Sept. Fungal-based compost (4 lb dairy manure-based vermicompost and 4 lb leaf-based compost) was brewed with 12 oz Fertrell Liquid Kelp, 4 oz fish hydrolysate (Organic Gem Liquid Fish 3-3-0.3 or Neptune's Harvest Benefits of Fish 2-4-1), and 16 oz humic acid (Fertrell Bio-Hume) for about 24 hour in a 60-gal Sotillo brewer. Compost tea was filtered, Nu-Film-P (6 oz/A) and fish hydrolysate (1 oz/30 gal) were added, then it was applied undiluted at low pressure (40 psi) using a nozzle with a large orifice that causes little resistance (FloodJet) using a tractor-sprayer. Rescue treatments were the OMRI-listed copper fungicide Champion, biofungicides Sonata (Bacillus pumilus) and Serenade (Bacillus subtilis), and mineral oil formulated as JMS Stylet-oil. These were applied 7 times beginning 27 Jul using D5-25 hollow cone nozzles on the same sprayer which was operated at 100 psi. These products were tested alone and/or along with compost tea.

Best control of powdery mildew was achieved with the resistant variety (Hobbit) and Champion applied to the susceptible variety Appalachian. In addition to less severe mildew, there was less defoliation, fewer dead plants, and more fruit with solid handles compared to other treatments. Neither Sonata nor compost tea suppressed powdery mildew when used alone. Compost tea also did not significantly improve control achieved with the powdery mildew resistant variety. Analysis of the tea revealed fungal activity was low while active bacterial biomass was in a good range. Although the leaf-based compost had very high fungal activity before the experiment was started, fungal activity declined over the season while bacterial activity increased. A tea with more fungal activity may be needed to suppress powdery mildew. Effective control with compost tea may necessitate modifying application timing, such as applying late in the day and/or starting earlier in crop development, perhaps including a seed treatment. When used with compost tea, Sonata, Serenade, and JMS Stylet-oil provided 50-71% control on upper leaf surfaces and 47-57% on lower leaf surfaces while control with Champion was 84% and 65%. Sonata applied with Champion did not improve control over that obtained with Champion alone.

Aerated compost tea and other alternative treatments for disease control in pumpkins

An experiment was conducted at Green Thumb Farm by Steve Storch, Earth Pledge staff, and Meg McGrath. Half of the plots were amended with ground basaltic rock before seeding. Foliar treatments applied weekly were compost tea, an OMRI-approved copper-based fungicide (Bordeaux mixture), and an elemental-derived silica spray. These treatments were compared to a water control.

Although pumpkins grown where basaltic rock was applied and receiving either the compost tea or silica spray appeared to be more vigorous than the other pumpkins, none of the treatments evaluated were documented to have a statistically significant benefit for suppressing any of the diseases that occurred (bacterial wilt, downy mildew, and powdery mildew) nor did they affect the yield parameters measured. This may be due to the fact that the biodynamic treatment made to the entire field in the spring had an overwhelming impact on disease severity and yield, weeds interfered with pumpkin growth and treatments, variables selected for measuring disease severity and yield did not capture differences that occurred, treatment timing was not adequate, and/or the treatments evaluated do not suppress the diseases that occurred.

Evaluation of biodegradable and photodegradable mulch on yield of cantaloupe

Athena cantaloupes were grown on three kinds of black mulch: biodegradable (Mater Bi), photodegradable and standard plastic to evaluate the impact on yield. Mater-Bi agro mulch is a thermoplastic material mainly derived from corn, wheat and potato starch. This was a non-replicated observational study. Numerically, the standard plastic produced the highest full season yield while early yield production was highest with the biodegradable mulch. No difficulty was experienced while laying the biodegradable plastic with a Buckeye mulch layer. The biodegradable plastic held up well during the season except under the fruit, which allowed the melons to be in contact with the soil. Therefore, most of the fruit harvested from the biodegradable plastic was discolored on the groundside with some melons having superficial insect damage. The biodegradable mulch performed as well as standard black plastic in an on-farm demonstration.

An evaluation of the Zea-Later® and Entrust for control of ear-infesting insects in sweet corn

Using the Zea-Later, Entrust 80W was applied at 1 or 2 oz/A* alone or with 2% Ultra-Fine Oil (*calculated based on delivery rate of 0.5 ml/ear, one ear per plant and plants spaced every ten inches in 34" rows). European corn borer pressure was low throughout the trial. Fall armyworm populations were moderate to low during the whorl stage and light later in the season. Corn earworm pressure was high during ear development.

All insecticide treatments provided significant control of corn earworm and higher levels of uninfested ears at harvest. There was no significant or apparent difference due to application rate of Entrust. Addition of horticultural oil was associated with noticeably higher numbers of uninfested ears at either rate of Entrust, although differences were not statistically significant. A large portion of damage assigned to the 'unknown' category indicates the Zea-Later treatments might be controlling some early ear infestations: in most cases 'unknown' damage was extensive, suggesting larvae reached older instars or completed development in these ears. A second treatment (after five days?) might significantly improve control. Foliar sprays, recommended for side-boring European corn borer, might also enhance control of corn earworm under similar conditions of high pest pressure.

Other Entomology Trials

Several other trials were carried out in 2004 to test insect and mite controls for organic production. These include tests with products such as E-Rase, Hexacide and others for whitefly control in poinsettia and control of spider mites in greenhouse production; evaluations with Metarhizium anisopliae for control of white grubs in container-grown plants and turfgrass and weevils in container-grown plants, demonstration with pheromone disruption for oriental beetle and rhododendron borer in nursery production and Entrust for flea beetle control in leafy greens.

The research team for these projects includes:

Meg McGrath, Vegetable Pathologist, Department of Plant Pathology, Cornell University
Dale Moyer, Vegetable Specialist and Agriculture Program Director, CCE, Suffolk County
Dan Gilrein, Entomologist, Cornell Cooperative Extension, Suffolk County
Andy Senesac, Weed Scientist, Cornell Cooperative Extension, Suffolk County

Contact Us:

3059 Sound Ave., Riverhead, NY, 11901.
Phone: (631) 727-3595
Or email Meg: mtm3@cornell.edu