- Vegetables: cucurbits
- Crop Production: application rate management
- Pest Management: row covers (for pests)
- Production Systems: general crop production
- Sustainable Communities: sustainability measures
The purpose of this project is to make use of a structure typically used for late and early season extension, known as caterpillar tunnels, during the hot summer months. Caterpillar tunnels are temporary or semi-permanent hoop structures. The ground support for ours are 1-3/8" galvanized pipe, used as top rail for chain link fence. Each 126" piece of pipe is cut into four sections and driven into the ground on five foot centers in rows 13 feet apart. A 20 foot piece of 1-1/2" pvc pipe is slipped over each galvanized pipe and bent to the corresponding pipe to form a hoop 13 feet wide and approximately seven feet tall. This structure resembles a small high tunnel without any base boards or solid end walls. A post is driven in at the end of each tunnel. For structural rigidity, a ridge rope is tied to one end post, wrapped around the top center of each hoop and tied to the post at the other end. The covering is also terminated at each end by tying to the same posts. Between each hoop, a stake, in our case a piece of rebar, is driven into the ground. These are used as anchors for overhead ropes to keep the cover in place. A sandbag is placed between the rebar and cover to keep the cover on the ground and to protect the cover from the cut end of the rebar. Peaks of the hoops and the valleys of the anchor ropes give the tunnel a segmented caterpillar-like appearance.
Making use of these structures during the summer will make them even more affordable to own by amortizing their use over a longer period. It is hoped that full utilization of these will increase farm profits. We are testing the suitability of shade cloth to cover these structures and comparing the results of the four fabrics. The shade cloths are all 50% shading and are black, white, red, and a reflective aluminized material. Kale and cucumbers were planted in each tunnel and an outdoor control crop through woven black ground cover. The ground cover is used to suppress weeds as cultivation within the confines of a caterpillar tunnel is difficult.
I evaluated each tunnel for its ability to exclude pests, improve working conditions, and increase yields. Random samples of plants were to be selected and monitored for pest pressure. Yields and internal air temperatures were recorded. Soil temperatures were also recorded as they could have an impact on plant performance.
The fabrics were left on the tunnels for the longest period possible in order to evaluate any shortcomings in durability.