Thistles

[Grayson Klassen]

A friend of mine has a certified organic farm where they grow hay and wheat. Lately they have been fighting thistles but can't use pesticides. Anyone know of a natural cure for thistles?

 

[smstonypoint]

A friend of mine has a certified organic farm where they grow hay and wheat. Lately they have been fighting thistles but can't use pesticides. Anyone know of a natural cure for thistles?

A mattock.

Steve

 

[Baby Grand]

Or some goats.

 

[oldnslo]

Depending on the acreage involved we used to use a #2 shovel and dig them out. You must get a fair portion of the tap root and dig them before they start to seed. Will probably take a couple years of persistance since the seeds last for awhile.

Roy

 

[nue2farm]

Try a small propane torch on them when it is safe to do so. DNR releases an insect that feeds on the seeds also. Dig them up and burn them too. Takes a long while to get them. Good luck.

 

[Mace Canute]

The eradication of the thistles would depend on what exact type they are. For example, Bull Thistle reproduces only by seed while Canada Thistle reproduces by rhizomes that are deep and exist below the level of normal cultivation and Sow Thistle roots can be as far as 10 feet below the surface which makes them difficult to eradicate also.

Regardless of what type, it's highly likely that it's going to be very labour intensive.

I know it would be difficult to implement and perhaps even unrealistic, but if you could swing it, boiling water is supposed to work good on individual plants.

 

[godaddy]

All I can say is "GOOD LUCK"! He better get on them before the problem gets to big. He'll always have to look every year to keep them under control.

 

[2manyrocks]

Vinegar as an Organic Weed Killer

I haven't tried it.


"a mattock." That's bad.

 

[Grayson Klassen]

A mattock eh? :laughing: Thats nice except very long process. The vinegar thing only works if you distill it to about 30% concentration or so he told me.

Thanks for all the replies, guess sometimes it sucks to be organinc and not be able to just use a bunch of round up

 

[smstonypoint]

Vinegar as an Organic Weed Killer

"a mattock." That's bad.

A mattock eh? :laughing: Thats nice except very long process.

A mattock was my Dad's favored method of keeping the farm free of thistles, but I was the one wielding the mattock.

Steve

 

[DAY]

Goats are browsers, and love thistles- at least the kind that grow here in PA! (I operated a goat dairy, until the therapy kicked in):laughing:

Ours reproduce by seed- wind born ("And up the chimney he rose, like the down of a thistle")- so constant mowing eventually gets the job done.

 

[Rob-D]

Canadian Thistle is on the invasive species list in the country. It's a monster! I have it here and the only way to get rid of it (we're organic) is to dig plants up before they go to seed.
I did read somewhere that it likes a specific soil but I can't verify that.

Rob

 

[forgeblast]

They are nasty here, and I do have to spray for them as part of my Crep program.
I found too that some birdseed will have them in it, which then just reseeds them.
I spray and hit them with the weedwacker a bunch of times.
I would think that the propane burners, or vinagar with salt mixed in it would wipe out just about anything.

 

[Rob-D]

They are nasty here, and I do have to spray for them as part of my Crep program.
I found too that some birdseed will have them in it, which then just reseeds them.
I spray and hit them with the weedwacker a bunch of times.
I would think that the propane burners, or vinagar with salt mixed in it would wipe out just about anything.

Yes, birds do like the thistle so I can see where they would spread seed.

Rob

 

[2manyrocks]

A mattock was my Dad's favored method of keeping the farm free of thistles, but I was the one wielding the mattock.

Steve

The messiest job I ever did on the farm was the time my Dad told me to dig out a small tree that had somehow managed to grow in the middle of the creekbed. I can remember the mud and water splashing everywhere when I grubbed it out with a mattock.

 

[Egon]

The good old thistle.

It has very deep roots and in reality is good for the soil as it brings nutrients to the surface.

It will propagate from roots or seeds.

But nobody like's it in their fields as it will predominate over desired species.

Back when before sprays on the farm they were controlled by regular deeper tillage and keeping the area black.

Dad had a home made V shaped cutter made old truck springs that was about four feet wide and cut maybe 16 inches deep. It was pulled by horses. It did work.

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Print this fact sheet
no. 3.108
Canada Thistle
by K.G. Beck 1 (Revised 11/08)
Quick Facts...
Canada thistle is a creeping perennial that reproduces from vegetative buds in its root system and from seed.
It is difficult to control because its extensive root system allows it to recover from control attempts.
Combining control methods is the best form of Canada thistle management.
Persistence is imperative so the weed is continually stressed, forcing it to exhaust root nutrient stores and eventually die.
Canada thistle (Cirsium arvense) is an aggressive, creeping perennial weed that infests crops, pastures, rangeland, roadsides and noncrop areas. Generally, infestations start on disturbed ground, including ditch banks, overgrazed pastures, tilled fields or abandoned sites. Canada thistle reduces forage consumption in pastures and rangeland because cattle typically will not graze near infestations. In 2002, the Colorado Department of Agriculture surveyed counties and while incomplete, the results showed more than 100,000 acres infested with Canada thistle (Figure 1).


Figure 1. 2002 distribution of Canada thistle in Colorado.
One plant can colonize an area 3 to 6 feet in diameter in one or two years. Canada thistle grows in a variety of soils and can tolerate up to 2 percent salt content. It is most competitive in deep, well-aerated, productive, cool soils. It usually occurs in 17- to 35-inch annual precipitation zones or where soil moisture is adequate. It is less common in light, dry soils. A survey conducted in 1998 showed Colorado has about 400,000 acres infested with Canada thistle.

Phenology

Figure 2. Emerged Canada thistle rosettes from roots in early spring.
Emergence. Canada thistle develops from seed or vegetative buds in its root system. Horizontal roots may extend 15 feet or more and vertical roots may grow 6 to 15 feet deep. Canada thistle emerges from its root system in mid- to late spring (late April through May) and forms rosettes (Figure 2).

The greatest flush of root-derived plants occurs in spring, but another flush occurs in fall. A flush can occur anytime during the growing season when soil moisture is adequate. This is particularly a problem when Canada thistle growth is disturbed by tillage or herbicides. This feature can be manipulated to the land manager's advantage.

Plants that germinate from seed do so at about the same time as root-derived shoots. Seedlings grow slowly and are sensitive to competition, particularly if shaded. Canada thistle seedlings develop a perennial habit (the ability to reproduce from their root systems) about seven to eight weeks after germination.

Reproduction and spread. Canada thistle begins to flower in late spring to early summer in response to 14- to 16-hour days (Figures 3, 4 and 5). Plants are male or female (dioecious) and grow in circular patches that often are one clone and ***. Female flowers produce a sweet odor and insects readily pollinate different sexed patches up to 200 feet apart.


Figure 4. Canada thistle in the late bud growth stage. Figure 5. Canada thistle in flowering growth stage.
Canada thistle develops seed sparingly. It may produce 1,000 to 1,500 seeds per flowering shoot. Generally, vegetative reproduction from its root system contributes to local spread and seed to long distance dispersal. Seed may be transported long distances by water, or attached to animals, clothing, farm equipment and other vehicles, and in contaminated crop seed. Also, wind may help disperse seed, but most often, the feathery pappus breaks off, leaving the seed attached to the parent plant to be dispersed by other means. Seed can remain viable in soil up to 22 years, and deep burial promotes survival longevity.


Figure 6. Canada thistle root system after 14 months growth from 25 vegative shoot cuttings.
Canada thistle allocates most of its reproductive energy into vegetative propagation. New shoots and roots can form almost anywhere along the root system of established plants (Figure 6). Tillage segments roots and stimulates new plants to develop. Shoots emerge from root and shoot pieces about 15 days after disturbance by tillage. Small root pieces, 0.25 inch long by 0.125 inch in diameter, have enough stored energy to develop new plants. Also, these small roots can survive at least 100 days without nutrient replenishment from photosynthesis.




Management
The key principle to Canada thistle control is to stress the plant and force it to use stored root nutrients. Canada thistle can recover from almost any stress, including control attempts, because of root nutrient stores. Therefore, returning infested land to a productive state occurs only over time. Success requires a sound management plan implemented over several years.

Cultural control. Grasses and alfalfa can compete effectively with Canada thistle if their growth is favored by good management. Maintain fertility and, if possible, moisture at optimum levels to favor grass or alfalfa growth. Soil analysis can easily determine fertility needs. Be cautious with nitrogen fertilizers, because excess available soil nitrogen may favor weed growth.

These are essential management steps to ensure optimum desirable plant growth and competition. However, competition alone seldom is effective against Canada thistle.

 

[DAY]

A local farmer has an overgrown, fallow field next door- absentee owner- that is a thistle monster. My friend mows it a couple of times a year, in self defense.

 

[dieselscout80]

A mattock was my Dad's favored method of keeping the farm free of thistles, but I was the one wielding the mattock.

Steve

I just put my son on that program too. :laughing::thumbsup:

 

[smstonypoint]

I just put my son on that program too. :laughing::thumbsup:

If he is anything like I was a youth, he isn't going to appreciate the experience.

Steve

 

[SandburRanch]

I have been told that cutting thistles in August during the waning moon phase will kill them. I've never tried that. I don't have thistles. I have sandburs and I'll trade for thistles any day.