In 1970 while on Sabbatical study leave at Landbouwhogeschool, the Dutch Agricultural University, in Wageningen, mentor Kees (C. T.) de Wit obm showed me a pasture where the only tillage for multiple years had been slit seeding of grasses and legumes into the clay soil. Good soil tilth and thriving vegetation was evident. His point was to eliminate plowing and disking, allowing vegetation to maintain soil health.
“In the first paragraph of the landmark 1943 book Plowman’s Folly, Edward H. Faulkner said, “The truth is that no one has ever advanced a scientific reason for plowing.” Nonetheless, 40 years after that publication cracked the foundations of agricultural science, most farmers still plow. Why?
“The most obvious (or at least the most frequently claimed) reason that soil is tilled is to loosen it so oxygen and water can reach the area where roots will grow. It seems logical that friable, loose earth would allow roots to spread evenly and to proliferate, and this is indeed the case. But using a moldboard plow doesn’t necessarily produce such soil. Plowing and disking a field results in a soil with broken structure lying atop a heavily compressed plow pan (the undisturbed layer that the plow doesn’t reach). This broken-up soil is very prone to being compacted by rainfall. In addition, many passes must be made over the field with very heavy equipment, the wheels of which further compress the soil. Untilled ground starts off being less compacted than a heavily machine-worked field, and it stays that way. What’s more, earth that has become compressed by tillage or machinery will return to a less compacted state after a few years of no-till planting. http://bit.ly/2iO52jf
Over the years I have read about minimum tillage or no-till management of soil and crops. Agricultural Engineering professional conferences have espoused the concept and supporting equipment. The most obvious example to my eye has been soybeans drilled directly into stubble as soon as wheat was cut, revealing strips of green in the golden standing straw visible from the road. Makes sense.
But I’ve never farmed crop or pasture acreage where I could try out the no-till concept. Articles emphasizing seedbed preparation, incorporating organic matter and fertilizer before planting seeds or transplants into my garden always led me to rototill as deeply as possible.
Cover crops I have also read about, but never practiced. Motivation and laziness are to blame. As a result each spring has found my beginning garden covered in dead crabgrass, weeds, fescue, etc., again encouraging rototilling to my mind, not wanting to burn and not willing to rake it off, thinking to incorporate what litter was there, so it would decompose.
Early this 2017 fall, after seeing cover crop seeds on http://sowtrueseed.com/, while chasing Bradford Watermelon seed, I began thinking about pursuit of a cover crop this winter on one or both of my bedded garden spots, one of which had not been cropped in 3 years.
My interest in garden winter cover crop was ratcheted up by a recent conversation with David Bradshaw, neighbor and retired well known Clemson horticulturist. His experimental winter treatment of Wrens Abruzzi Rye and Crimson Clover, knocked down and spring incorporated, resulted in yields of okra, cucumber and squash as I remember it, with no additional fertilizer, comparable to those under recommended rates of 10-10-10. The combination of N from the legume (peak when crimson clover heads begin to turn red) and decomposition of the biomass from the rye provided what the crops needed. Sustainable farming to my mind.
Browsing uncovered http://brownsranch.us/ emphasizing cover crops and zero-till. Gabe has increased organic matter content in North Dakota from 1.9% to 6.1% over the past 20 years, and infiltration rate from 0.5 to 8 in/hr.
“Today, the Brown Ranch includes about 3,000 acres of restored native rangeland and improved pasture producing cattle, pork and poultry, and 2,000 acres of no-till, cropland producing corn, peas (grain and forage types), spring wheat, oats, barley, sunflowers, vetch, triticale, rye and alfalfa, plus a great diversity of cover crops. No insecticides or fungicides have been used on the ranch for over a decade, herbicide use has been cut by over 75 percent and no synthetic fertilizer has been used since 2008. Corn yields average 20 percent higher than the county average. http://bit.ly/2iMlXD5
“Mycorrhizal fungi grow in healthy soils and are responsible for nutrient transfers between plants and soil biology. The most critical thing in a plant’s life is its relationship with mycorrhizal fungi, which is why tillage and synthetic chemicals should be avoided. http://bit.ly/2iOtjpw
And, earthworms proliferate under no-till practices. See http://bit.ly/2iRDCt9.
“Earthworms have significant impacts on soil properties and processes through their feeding, casting, and burrowing activity. The worms create channels in the soil, which can aid water and air flow as well as root development. The shallow-dwelling worms create numerous small channels throughout the topsoil, which increases overall porosity and can help improve water and air relationships. Nightcrawlers create large vertical channels, which can greatly increase water infiltration under very intense rainfall or ponded conditions. Nightcrawler channels can also aid root proliferation in the subsoil, due both to the ease of root growth in a pre-formed channel and the higher nutrient availability in the cast material that lines portions of the burrow. Earthworm casts, in general, are higher in available nutrients than the surrounding mineral soil, because the organic materials have been partially decomposed during passage through the earthworm gut, converting the organic nutrients to more available forms.
Earthworms improve soil structure and tilth. Their casts are an intimate mixture of organic material and mineral soil and are quite stable after initial drying. The burrowing action of the worms moves soil particles closer together near burrow walls, and the mucus secreted by the worms as they burrow can also help bind the soil particles together. Increased porosity, plus mixing of residues and soil, are additional ways that earthworms improve soil structure. http://bit.ly/2iOUd0D
So, my next question is how to incorporate cover crops and no-till into my vegetable gardening.
I like the results of David Bradshaw, so after rototilling with skid steer, have mixed Crimson Clover seed and winter rye (not Wrens Abruzzi) into 5 pounds of grits and dropped the mixture, using a Scotts Turf Builder Classic Drop Spreader, onto the two 8-ft wide beds above the bee hives, about 60 ft long. Those beds had been built wide 4 years ago so I could rototill them, and had added bark mulch and horse manure. After sowing I rolled the area with the wide tires of the lawn tractor to get soil-seed contact. Soil was damp. I was late, sowing late October, but germination was fine. Rye is now 2 – 3 inches tall; clover has put on true leaves.
I also rototilled the bamboo infested beds above 130, about 2 weeks ago, and ordered Wrens Abruzzi Rye from Hancock Seeds near Dade City FL. I sowed the remaining 1.5 lbs Crimson Clover and about 3 lbs Rye today after another light pass of rototilling. Rolled as above. Yes, I’m late. Beds are of similar size.
I also rototilled the 10-20 ft wide strip between driveway and bamboo, same day, and today sowed 3 lbs Austrian Winter Peas (by hand; seed would not go through seeder) and 3 lbs Hairy Vetch. We’ll see how deer respond.
Question: How to knock down the vegetation next year and seed?
“So, you’ve harvested the veggies from your garden and planted a mixture of cover crops in their place in order to protect and nourish the soil. How do you make the transition back from cover crop to your chosen vegetables the following season? It might be tempting to till and turn those cover crops over into the soil, but this is the last thing you should do. You do need to terminate the cover crop somehow though. There are a number of different ways to do this. You could:
- Stomp the cover crop into the ground with your feet or a board (simply attach two rope handles to a 2×4 board and then use the board to step down the crop)
- If the cover crop has started to form seed heads, you can kill it off by rolling crop roller or small barrel over it
- Cut the growth down and leave the residue on top (although it works better if it’s rolled or stepped down)
“Once the cover crop has been killed off, you’re ready to plant your vegetable seeds. For a small garden, Gabe recommends using a hoe to part the cover crop remains over to the side. Create a small slice in the soil, drop in your seeds and cover with a small amount of soil. If you’re planting a transplant, simply move the cover crop aside, dig the hole and plant as normal. http://bit.ly/2iMBS48
With the heavy biomass litter I expect, using a hoe seems laborious. So how to get seed in the ground? Transplants I can see. But seeds?
My father had what is now called a jab planter, whereby one or a few seeds are dropped from waist level down a tube into a divot made by jabbing the tool into the ground. He used it to plant watermelon, in hills. I haven’t found one like his, but do find that Forest Service evaluated four similar at http://bit.ly/2BanXMb, preferring the Hatfield Transplanter, http://bit.ly/2iN1lKQ, apparently available only from Johnny’s Seeds, and Almaco Hand Jab (expensive).
A jab planter might work well for hill dropped seed. But things like beans, at close spacing, ? Planet Jr? Through the litter?
Crabgrass, brought in with horse manure, and perpetually reseeding, has been much more problematic than weeds in my gardens. I may try Treflan watered in by rainfall next spring. “A one-half inch rain or its equivalent in sprinkler irrigation must be received within 24 hours or poor weed control will result.” It is labeled for Asparagus, Carrot, Celery, Cole Crops, Cucurbits, Okra, Pepper, Potatoes, Southern Peas, Tomatoes, Beans, Greens, and Green Peas. See http://bit.ly/2BaKf07.
Jerry’s Journal # 19 • 24 November 2017
PS: An eBay search yielded several “corn planters” for sale. I have bought one out of Kansas, yet to be seen. An internet search also yielded http://bit.ly/2zLhg2Q. So we’ll see. 3 December 2017