[7/3/13 update] --
Recent scouting of the spring planted barley fields shows a thin stand compared to some of the neighbors. I contacted a crop specialist and a plant pathologist to evaluate the fields.
After seeing a plot with no fall applied glyphosate (see post title-- "importance of fall chemical treatment"), I was sure that we had a serious case of Rhizoctonia, -- and I expected it from past experience of seeding into green plant material (poor field sanitization).
In all cases where we checked, Rhizoctonia, if present, was a small part of the problem. Testing will be done for plant diseases; however, the problem seems to be connected to planting depth, and compaction. In all locations checked, seed was placed too shallow in the soil profile for early root development and crown establishment. In all locations checked, the (shovel depth) soil profile showed multiple compaction layers. Although these layers did not appear well defined, the roots have grown in mass, on horizontal planes, with restricted vertical growth. Vertical root growth present appeared to traveling along old root channels and worm holes. This crop will not utilize a lot of the 4 foot soil profile. These fields have been continuously no-tilled for 20+ years with vertical disturbance limited to the depth of hoe opener on a single pass drill.
It was noticed that there was a lot of stubble left standing. The barley heads had finally grown above the WW stubble so the field looks pretty normal. There was a discussion on whether stubble should be left standing or be flat following seeding. Research shows that standing stubble intercepts very little of the total amount of light energy; however, it does intercept some of the wave lengths, resulting in taller plants with fewer tillers. I observed this condition in our spring barley fields.
We will have to live with this crop; however, the good news is that these issues are relatively easy to fix. The Cross-slot drill has proven that it can cut through tall, very heavy residue, even that which is matted down, with out plugging or pushing. We need to monitor the depth setting more closely. We may have to map the residue, creating zones where it is necessary to change the depth setting. For the compaction, we will introduce a cultivar with a tap root (mustard, canola, garbs, alfalfa) as part of our crop rotation. For the light intercept, we will incorporate a method to lay all the stubble down (plate, closer opener spacing, wider packers, segmented roller, ??). Whatever we decide on, it will not create surface disturbance. The heavy undisturbed residue proves to be a very good deterrent to weed emergence. This is all good news for our concept of an ultra-low disturbance seeding system. This experience probably goes a long ways in answering the question in the past of spring crops not doing well for us. Winter crops do well because of the extra grow time to overcome the compaction issue. We did experience significantly better wheat crops following mustard several years ago. Diseases don't appear to be a factor for us to be concerned with. Attention directed to making sure we have the seed at the proper depth for root and crown establishment appears to be critical for success in spring cropping. We need to grow a tap root crop on all of our ground as quickly as possible and put it in as part of a regular rotation.
[6/5/13 - update] --
MUSTARD @ St.John: Most of the field is developing fine. There are holes in the seeding and the very heavy area west of the shop is poor and will be destroyed in the near future. Bloom has started
At Thornton: This field is developing well. There appears to be fewer holes in the seeding. We just destroyed 6ac along the drainage ditch that never received the preparatory spray this spring because of surface water. Blooms are not showing yet.
I am please with the seeding in general. The drill penetrated the very heavy residue, which was a concern prior to our seeding. The stand shows areas where we were not deep enough, or didn't hold enough disc pressure, to get the seed into soil. Some was left on top of the soil under the residue.
SPRING BARLEY @ St.John: Most of the field is developing fine, and jointing. There are holes showing in places, and an un-even development. We are still seeing new plant emergence. This is also mostly do to inoperative depth sensors giving an inadequate average across the drill. We undoubtedly should have set the drill a little deeper, even if the depth sensors had been operating properly.
At Thornton: Very much the same as St.John. The flat along the creek is doing very well. When we seeded it, I didn't think this would emerge through the very deep matted residue. The drill did cut through the residue, but left significant amount of seed on the soil surface under the residue matt. This shows that seed doesn't need to be in the dirt to germinate and grow well if the matt provides the environment for seed germination and emergence. The crown is set high. Will the residue matt protect it when the weather turns dry and hot.
[5/25/13 - original post]
At St. John, I inspected the mustard and barley planting.
Mustard:-- Earlier, the decision was made to replant and turn in an insurance claim. Neighbors have reseeded their fields to the east and west of us. Our decision was based on the flat area west of our shop. It looks poor, with few viable plants visible. Pithium and freeze damage were obvious and it appeared that seed may not have reached dirt in areas. Today, the tale is different. There are some small voids throughout the field, but generally, it is an excellent stand, except the flat west of the shop. We will either fallow ≈10ac or seed winter canola later in July for harvest in 2014. At this point, stand density and growth difference was not distinguishable between the areas with tall stubble, and areas with flat stubble. We'll keep watching.
Spring Barley:-- 99% of the field looks very good. ≈1% has nothing but matted golden residue. It appears that those areas, which are in draw bottoms, had sufficient depth of matted residue where the drill was not set deep enough to get the seed into dirt. It is rowed up on the soil surface under the residue. This is a condition that we will have to address in the future. The options listed in an earlier post are still potential solutions.
I will provide pics of these two fields in the near future.
No comments:
Post a Comment