- Vegetables: peppers, cucurbits, tomatoes
- Crop Production: intercropping
- Education and Training: on-farm/ranch research
- Farm Business Management: whole farm planning
- Pest Management: biological control, trap crops, traps
- Production Systems: holistic management, organic agriculture
The Brown Marmorated Stink Bug (BMSB) is an invasive pest causing significant economic losses to farmers due to its extremely broad feeding range and lack of native natural enemies. All major vegetable and fruit crops are susceptible to BMSB, and the predominant management tactic being employed is frequent application of broad-spectrum insecticides that are toxic to beneficial organisms, disrupt biological control and lead to secondary pest outbreaks. This project explores an innovative non-chemical approach that combines a highly attractive trap crop buffer with commercially available baited stink bug traps to manage BMSB. The overall goal is to enhance the economic viability and environmental sustainability of farms currently endangered by BMSB, by increasing yields and profits and reducing the volume of broad-spectrum insecticide applied to the environment. Our system involves enticing BMSB to a crop strip that remains attractive throughout the growing season, and then luring them into pheromone-baited traps, where they desiccate and die. The project builds upon current BMSB knowledge and preliminary data collected for more than 50 crop varieties on our farm. The trap crop will consist of a perimeter planting of green amaranth and sun flowers, both highly attractive to BMSB nymphs and adults at our farm. We will test this system in replicated field plots containing four highly valuable crops that are exremely susceptible to BMSB: okra, sweet pepper, tomato and summer squash. We will then share our findings with other farmers, extension and agricultural professionals through websites, presentations at professional meetings and on-farm demonstrations.
Project objectives from proposal:
The research aims to enhance environmental stewardship by providing a pesticide-free, non-toxic tactic for managing BMSB, eliminating application of toxins to our food, habitats and soil and water resources. Furthermore, we aim to enhance farm profits by reducing BMSB damage to four major cash crops and by significantly increasing salable yields.
The proposed study will use a randomized complete block design (two replicates per block) to test the effectiveness of an integrated trap crop and baited pheromone trap system in protecting four economically important vegetable crops: okra (‘Clemson Spineless,’ High Mowing Organic Seed Co.), sweet pepper (‘Red Ace,’ Johnny’s Seeds), tomato (variety Johnny’s Seeds), and summer squash (‘Zephyr,’ Johnny’s Seeds). These crops were chosen based on their high level of susceptibility to BMSB and their compatibility in terms of culture. The farm has two natural blocks based on previous use: Block 1 consists of two adjacent fields (~5 acres each) that have been planted in a highly diversified rotation of vegetables, flowers, herbs and small fruits since 1998; Block 2 consists of two adjacent fields (~10 acres each) that have been in a corn-soybean-hay rotation since 1998. Both blocks are adjacent to hardwood forest stands. Four study plots (900 sq ft each) will be established within each block, for a total of eight plots. Each study plot will contain 4 linear crop rows (each 3 x 30 ft) with aisles in between (3 x 30 ft aisles; See Figure 1). Half of the plots within a block will be randomly selected to receive BMSB treatment and the other half will serve as controls. The BMSB treatment will consist of a 3 ft wide border strip of trap crops [green amaranth (Amaranthus spp., Redbud Farm saved seed from 2011) and sunflower (‘Velvet Queen,’ Johnny’s Seeds)] planted to form a perimeter around the vegetable crops (See Figure 2: 1 replicate). The perimeter trap design has been selected because, while it is generally thought that BMSB emerge from the woods in spring, we do not know for certain from which direction they will immigrate; therefore, we need to protect all sides of the vegetable crop plot. Control plots will be exactly the same as treatment plots but will not have the border strip of trap crops. The study will use a total of 8 field plots, with 4 designated as BMSB treatment plots and 4 controls.
Vegetable Crop and Trap Crop Perimeter Establishment
The vegetables will be propagated by farm owners Clarissa Mathews and Haroun Hallack, with assistance from a field hand, according to standard practices that we have used at our farm for more than 10 years. Specifically, the sweet peppers, tomatoes, and squash will be started as seedlings in the greenhouse in late February, 2012. The soil will be prepared (plowed and disked) in April, with the specific timeframe dependent upon on weather and soil moisture conditions, avoiding working the soil when too moist. A total of four 3 x 30 ft rows per plot will be prepared with a 6 ml irrigation drip tape down the middle and covered with 3 ft wide black plastic (1 ml embossed, Martin’s Produce Supply). The sweet pepper, tomato and squash seedlings will be transplanted by hand into the black plastic during the last week of April, with the specific days dependent upon on weather and soil moisture levels. Okra seeds will be direct planted into holes punched through the plastic in early May (3 seeds/hole, later thinned to 2 plants/hole). The crop configuration will be identical in each plot and is based on the light requirements and typical height attained by each crop; rows will be oriented from West to East, with okra at the North end of the plot, followed by tomato, then sweet peppers, then squash at the South end of the plot (Figure 1). Tomato, okra, and sweet pepper plants will be spaced at 18 in, totaling 20 plants per row; squash will be spaced 24 in (total 15 plants/row). Compost (~2 cups) will be added to individual holes that have been punched in the plastic (all crops). For frost protection during the first month, rows will be covered with floating row cover (AG19, 0.55 Oz/Sq Yd) supported by wire hoops (3/16” high tensile steel, 76” long) placed every 3 ft. Tomatoes will be caged in early June (36” high metal cage, 1/plant). The aisles between rows will be mulched with straw to discourage weed growth. Irrigation will be applied via the drip tape through the season, as needed. No insect control will be used. The 3 ft wide trap crop border will be direct seeded during the first or second week of May. Sunflower seeds will be sown with a push seeder (~2” spacing) to form the interior row of the border strip; amaranth will be broadcast by hand to form the exterior edge of the trap crop border strip. Following germination, trap crop plants will be hand watered as needed to ensure healthy establishment.
BMSB Trap Establishment in the Trap Crop Perimeter
During the first week of June, four ‘RESCUE’ stinkbug traps (Sterling International, Inc.), using inverted funnel/pyramid design and baited with dual pheromone lures, will be placed in the trap crop border of each treatment plot. This timeframe corresponds with emergence of the first generation of BMSB in our area (typically in mid-June). Control plots will not receive stinkbug traps. The RESCUE traps will not be used to monitor BMSB population densities; rather, they are intended to capture BMSB out of the trap crop, before the pest immigrates to the vegetable crop area. A RESCUE trap will be placed in the middle of the each side of the trap crop border (See Figure 2). According to the manufacturer, a RESCUE trap is capable of attracting stinkbugs within a 20-30 ft radius; therefore, a minimum of 30 ft buffer area will be maintained between any two study plots to avoid attracting BMSB out of control plots (See Figure 2). Traps will be hung from stakes at a height of 3 ft and secured at the bottom to enable juvenile capture. The trap contents will be emptied weekly through the season, and lures will be replaced every 7 weeks, per manufacturer’s recommendations. Traps will be installed, serviced, and monitored by Clarissa Mathews and a field assistant trained specifically for these tasks.