[Update: 7/2/15] Since the demonstration the weather has been hot and dry. Part of my interest in the demonstration was to see what happened to seed zone moisture. The "configuration" stated below has a broad meaning including opener type, closing disc's, packer wheels and their relationship to the opener. The plot started with excellent moisture and good ground cover. a)--Narrow hoe,--the configuration left an open seed trench that wicked off the moisture. b)--Wide hoe,--the configuration powdered the surface soil. The ground dried to the bottom plate of the Anderson opener. A deeper depth would probably provide the dust mulch to hold moisture for seed germination. c)--Double Disc,--the configuration provided a lot of tillage. There was significant loose surface mulch that dried down to the firm soil. A deeper depth will probably hold moisture for seed germination. d)--Angled Single Disc,--the configuration did not firm up the slot, and moisture was lost where soil had been lifted by the disc. A packer that firmed the loosened soil would probably hold moisture for germination. e)--Single Disc with inverted T,--the configuration held moisture the best. As advertised, if the integrity of the slot is not compromised (left open), very little moisture escapes. Unfortunately that's easier said then done.
All of these designs are good direct seed drills. The effort applied for successful seeding will vary with the unit. The old rule of thumb still applies, --disc drills work better in standing stubble compared to flattened stubble, and hoe drills prefer stubble length to be less than the row spacing.
June 23, was a warm day. Seventy five people braved the heat and dirt to see five drill styles tackle the field of mowed and standing stubble. The event was put on by the Palouse Rocklake Conservation District. There was a good mix of farmers from a 60 mile radius, University and USDA people, and two dealer representatives present. Floor Dry was used in place of seed and that turned out to be a good substitute. The white color contrasted well with the brown dirt, and we won't be fighting volunteer cultivars all summer and early fall.
A WSU researcher reported on their studies with the Stripper Header at the Lind, WA station. In general, the tall stubble keeps the ground warmer in the winter and cooler in the summer. Air velocity across the ground surface is significantly reduced with the longer stubble, which helped keep the boundary layer of high humidity at the soil surface. In short, these factors reduce the rate of evaporation off the soil surface. As reported in an earlier post, evaporation is approximately 83% of our moisture use/loss. Two weeks ago we placed four HOBO temperature sensors in the ground, --a) under a board firmed to the ground, b) under heavy mowed residue, c) under residue in tall stubble, and d) in bare ground with all surface residue removed, but untilled. We will read them this fall and again next spring. We have verified these results last year with our HOBO's. This is an excellent site to add data for further verification.
Grower experience with the stripper header indicate that increased capacity of older combines can be expected. The stripper header is excellent in small grains. We have harvested mustard with success. We will attempt peas and garbs this year. Theoretically the stripper header will harvest any crop that will fit under it's hood.
Field background: The field has been Direct Seeded for 23 years with no residue manipulation other than mowing. No harrowing. The plot has 2014 winter wheat residue that had large areas mowed. Most of the area has good ground cover plus the 2014 crop residue. The residue is very dry, and the ground under it has good moisture. The seeding area is complex with variable soils and variable residue conditions. In the pic below, from left to right is the CrossSlot(single disc w inverted T), JD750(single disc w 7 degree angle), Horsch/Anderson(≈ 5"wide hoe), AgPro(≈1"narrow hoe), Palouse Zero Till(double disc). All the units were designed as single pass drills, applying both seed and fertilizer. Each drill made two passes with no changes from the original drill setup.
Results: All the drill types were able to seed through the standing and mowed residue for the short distance encountered in the demonstration. Some clumping and shedding of residue was noticed behind the hoe drills. Each hoe drill did have a straw bridge at some point in the demo. With the conditions as dry as they were, the disc drills ran easily through both the standing and mowed residue. Straw tucking was evident, but probably not an issue with any of the disc drills. The CrossSlot, with it's inverted T slot rarely show any effect of straw tucking even though that is the signature look. The seed is tucked to the side in the T slot away from the straw. The appearance of straw tuck helps eliminate sealing of the surface, making it easier for the coleoptile to emerge from the soil, while at the same time, sealing in the high humidity environment around the seed. This design, if the slot closure is not compromised, allows seed to geminate in a lower moisture environment than other seeding systems.
Pic above shows producers looking at the placement of the Floor Dry, and the approach of the Palouse Zero Till drill on it's return pass.
One point of interest to me was the comparison of the CrossSlot with the JD750. I have always accepted the idea that the JD750 was the lowest disturbance drill where it cuts-lifts-drops the soil in place. However, the CrossSlot definitely left the field looking as if it caused less surface disturbance, and left the residue tighter on the surface. Did the JD750 disturb more soil, and sift more seed through the residue onto the soil surface? That is questionable. Maybe time will tell. Green growth and soil disturbance go hand in hand. The more the disturbance, the more the green growth.
A surprise to me was, which drill did more processing of the residue, and the soil surface. I assumed that the Horsch, with it's wide hoe and recovery disc's to backfill the seed trench, would be the clear winner; however, the Palouse Zero Till with it's close row spacing may actually be more aggressive. I think the green-up will decide the winner.
All in all, I was pleased with the demonstration. Hopefully the drill participants, along with the attendees learned a little, should they develop an interest in a stripper header. It needs to be kept in mind that this was a relatively light crop with shorter than normal stubble height. I hear that Shelbourne has recently doubled their manufacturing capacity, so, interest is apparently building.
