Clearing a Field of Canada Thistle in Preparation for the Next Crop
Andrea Hazzard, Hazzard Free Farm, and First Hand Harvest CSA, Pecatonica, IL
“Five acres in organic vegetables which has been fallow for 20 years. 195 acres is in conventional corn/soybean farmed by my father and brother and 40 acre in CRP. 2009 will be year-3 of the vegetables, 125 Varieties grown, I intend to incorporate 100 Turkeys this year. I am trying to develop rotations but keep adding acreage. I do have a rotation set up for part of the garden. It is a modified 6-year rotation. I want to incorporate inter-row cover crops mainly small white clover, and have been looking into roller crimpers. Soil is mixed, some is really rich bottom land and some is a bit sandy, I compost, but it’s never enough to go around. I have access to wood chips/horse manure but have not pursued it yet. Weeding... I want to go to raised 4-5'w beds and do more with stale seed- bedding, we will be trying out a lilliston weeder, and I have a one row cultivator for the corn. I also do newspaper/straw on my permanent beds. I use several rototillers, running them shallow as well as hand weeding and scuffle hoes."
The Hazzard Free Farm is an fruit and vegetable farm
Production approach: Natural (chemical free)
Rotations: Long-time pasture going into raspberries or pumpkins
Cover crops: Clover, triticale, oats, peas
IPM used: None
Tillage: Cultivator, plow, lilliston, rototiller
Soil amendment program: Presently nothing, but manure and compost
Soil tests: Click HERE.
Field was visited 5/12/09. Soils were were in good condition. Canada thistle was observed in two different areas of the farm -- existing strawberry beds, and in an old pasture that Andrea plans to put into raspberry beds or pumpkins. Andrea has access to hand labor and is managing thistles in the strawberries with diligent hand-digging. She may mulch with chopped sudangrass. The main field chosen for the project is the abandoned pasture. Thistle was growing thick in the tall grass (see photo below), but was still no where near flowering. She will try the following strategy this year and hopefully clear the area of thistle in preparation for a healthy, weed-free crop next year. The following plan was developed with Andrea:
1. Till multiple times. Starting immediately with a rototiller, 2-3x before planting sudan grass.
2. Plant sudan grass. Seed will be located and sudan grass will be planted in early June at a recommended rate of 55 lbs/acres in area tilled.
3. Mow and graze sudan at 4-6'. Sudan grass will be mowed or grazed just as thistles are starting to flower. Sudan should be at least 4' tall.
4. Sudan will be mowed again. A second mowing will prevent any thistle from flowering and help build up a thick layer of biomass to smother thistle.
5. Sudan will be tilled under in Fall or following Spring.
Andrea had the area mowed in early May, and tilled around May 15. June 15 she cultivated the thistles again and two days later planted sudangrass.
Even though the sudangrass was planted a little late, it had grown well and was 6 feet + on August 31. Andrea planted the sudangrass very heavy, broadcasting and dragging it in. The sudangrass choked out all weeds. The picture below shows two different treatments in the test area. The area tilled but not planted to sudangrass was very thick with pigweed.
There was still thistle present on the edge of the sudangrass plot outside the sudangrass area. Andrea will mow the sudangrass in early September.
Sudangrass (left), tilled w/o sudangrass (center), fallow (right)
Thick-growing sudangrass effectively suppressed C. thistle and other weeds.