In meetings with organic rice producers there is a common theme – we need to increase organic nitrogen fertility and control weeds in rice! The two most often mentioned weeds in rice (outside weedy or red rice) is Hemp Sesbania and Northern Jointvetch.
These weeds are very similar in appearance, at least as very young plants and both are problems throughout the semi-tropical areas of Texas to Mississippi. Hemp sesbania can grow to be so bad that you can’t get the combine through, and those portions of the field are just abandoned.
In doing a little research I found that the fungus Colletotrichum gloeosporioides f. sp. Aeschynomene packaged and labeled as LockDown Bioherbicide, is very effective on Northern Jointvetch and has been effectively used in Arkansas rice fields for many years. Now Arkansas rice farmers don’t have a real problem with Hemp Sesbania but in researching the fungus I have found several research reports that show this fungus can also be very effective against Hemp Sesbania (download report below) if used with Silwet L-77 Super Spreader (or equivalent OMRI Approved spreader/sticker).
The company that formulates LockDown herbicide is small and orders for the bio-herbicide fungus have to be made in advance so that it can be “brewed” and ready to apply. Cost is less than $15 an acre. It is a bioherbicide with nothing but fungal material in the product. Certified organic operations would need to get approval from their certifier before using. (LockDown label below)
If any organic rice farmer is interested in applying LockDown Herbicide to control Northern Jointvetch and/or experimenting on Hemp Sesbania control, please let me know. We will be getting an order ready and picking up the Lockdown Bio-Herbicide for growers later this spring.
The Organic“Get Together” will be held on Tuesday, February 21, at The Armory on 101 Webb Street in Brownfield, Texas. Registration starts at 1 pm and program starts at 1:30 pm.
This “Get Together” will be a chance to hear all about organic cotton, peanuts, markets, crop problems and solutions, organic programs and more. Speakers will include Dr. Justin Tuggle on organic crop updates, Dr. Carol Kelly with a cotton variety development update, Dr. Dylan Wann to discuss IPG peanut development, Dr. Emi Kimura with a crop overview, Dr. John Cason with an update on interesting developments in peanut drought tolerance, Dr. Holly Davis with a discussion on management and use of organic pest products, Brandi Chandler with an update on organic certification and Bob Whitney with organic program updates.
Organic product companies will be introduced and give a short update. These companies include Certis, Pro Farmer, APF, TPPB, Texas Earth, Green Dirt, Kunafin, IPG, Golden, Dragon Line, Nature Safe, and All-Star Peanut.
The “Get Together” will start with registration at 1 pm at The Armory and the program begins at 1:30 pm and lasts till 4 pm. No meal, just a snack break is planned!
Texas TOPP is a five-year partnership program designed to effectively recruit, train, mentor and continually advise farmers who want to transition to organic production. Its overall goals are to build up successful Organic Farmer to Farmer Mentorships that are a part of a larger Organic Community Building program. Within this community will be developed organic resources available to both transition and certified growers, mentors, allied industry, and agencies that provide the needed help and support to a growing Texas organic movement. This Technical Assistance and Training will benefit both certified organic and transition organic while strengthening the overall organic program. Outside of this effort and yet integral to long term success is a Workforce Training and Development effort that focuses on how best to train future organic industry professionals.
Texas TOPP as a partnership program will be led by Texas A&M AgriLife Extension and the overall AgriLife OrganicProgram but with special partnerships that include Texas’ higher education institutions, USDA agencies, nonprofit organizations, and farm associations. Efforts of all participants will interact and impact conventional farmers, transitional organic and certified organic farmers and the many allied industry supporters of organic in Texas.
Texas TOPP will emphasize and solidify a commitment to organic agriculture by Texas A&M AgriLife Research and Extension and help ensure the future of organic within Texas agriculture for generations to come. More information will be coming but Texas Topp has already begun!
As compost and manure use is more common because of the high cost of chemical fertilizers we are seeing some of the weeds that are associated with cattle feeding starting to appear in our fields. This is one of the culprits Common Mallow and it is one you can easily recognize – it gets everywhere!
This past spring, I bought some compost to use in my yard and garden areas and it has been a great product to use. Of course, we have not had a lot of rain or cooler weather since late spring, and I never noticed any real weed seeds from the compost. I was very hopeful I had escaped the problem until fall! When we got some rains, and some cooler weather here comes the mallow with a vengeance.
The fortunate solution came at Christmas time when 8-degree weather killed it to the ground and no more has come up since. Does that mean my invasion of mallow is over – far from it! It will be back in spring and with a vengeance but a hoe or even an organic weed control product will take it if I start very early.
“Ten years ago, only about 10 million acres in the U.S. were planted with cover crops. Today that’s up to about 22 million acres, and the number is increasing by about 8% annually.” This is a quote from this article on the ancient farming practice of cover crops (click here for article). Certainly, organic farmers are familiar with and use cover crops and in our “Great Plains” region the Organic Farming Research Foundation has survey results that show over 85% of you use cover and green manure crops in your organic operation.
Because we use and need cover crops and because I give organic programs on cover crops, I try to read all the research I can and occasionally I find something that just “tickles the brain.” I accidentally came across a study done at New Mexico State University in Las Cruces entitled, “Fall-sown small grain cover crops for weed suppression and soil moisture management in an irrigated organic agroecosystem” in the journal Renewable Agriculture and Food Systems. (Click the image to read the study)
It is a very interesting read but in summary they conducted the trials over several years with many different cereals and found that the barley varieties gave the best weed suppression and least soil moisture losses. Here are a few quotes from the results:
In our study, earlier maturing varieties (‘Robust’, ‘UC603’) also displayed high levels of weed suppression. The apparent relationship between early maturity and weed suppression ability suggests that time to canopy closure is a significant cause of differences in weed suppression among barley varieties.
Our study demonstrated that a barley cover crop did not deplete the soil moisture, and during one season (2016–2017) actually conserved it following a long dry period (Figs 1 and 2). The beneficial ecosystems services demonstrated in this study may help reduce the hesitancy to incorporate cover crops into southwestern irrigated cropping systems.
The varieties ‘Robust’ and ‘UC603’ did an excellent job of weed suppression during two seasons. Thus, these barley varieties (‘Robust’ and ‘UC603’) are recommended for organic cropping systems in southern New Mexico and similar semi-arid environments.
These recommended barley varieties could fill the need for a ‘non-thirsty’ cover crop in the southwestern United States and play an important role in the effective management of weeds in organic production systems.
In summary the barley varieties they planted had far less weeds than in the unplanted control (less than 5 weeds per square meter (11 square feet)) and soil moisture in the unplanted control (bare ground) was consistently less than the soil moisture content in the barley plots. Not bad and something that should make us want to plant some barley!
Field bindweed is one of those weeds that can seem like a slight problem, something you could just pull up or hoe out and be done – WRONG! Field bindweed is a perennial weed with an extensive root system and a fast-growing top to match. One vine can grow 3-4 feet and it easily grows to the tops of field crops and begins to cover them. Its roots grow equally as fast and if you hoe or chop it out the root pieces just grow a new plant!
The seeds are small but not as small as many others and certainly not as small as pigweed. What makes this weed a real problem in field crops is the fact that plowing spreads the seeds and root pieces so that soon the entire field is covered in field bindweed. Why is it not a problem in pastures or grazed crops? Simply cattle love it! They will continue to eat the weed down and without leaves to make carbohydrates the plant eventually starves to death. The use of grazing is a key to regenerative agriculture, and this is one of the reasons – weed control.
Is there a bioherbicide we can use in organic crop farming? Potentially yes, because over 3 decades ago some researchers found a fungus causing damage to the leaves of field bindweed – Phomopsis convolvulus. This fungus actually carries the title convolvulus as part of its name which is part of the scientific name of field bindweed – Convolvulus arvensis. In this experiment they grew out the fungus and sprayed low to high concentrations of the fungus on various stages of field bindweed growth. Overall, they found that the fungus did kill the leaves but that the extensive root system had enough energy to put out new shoots. Two or more applications are suggested very similar to what is recommended when spraying any chemical control products.
This type of research into bioherbicides is progressing at a fast pace nowadays owing to the lack of chemical herbicides and weed herbicide tolerance. These developments are a big help to the organic grower who can use an organic approved herbicide when nothing else works – and unfortunately field bindweed can easily fit that category.