|
Little River, TX | By this I mean the adverse chemical effect varies according to soil, climate, and plant species involved.
At least here in the CenTex curly dock will get rid of any other plant within an amazing distance. With this we have true alleopathy.
Now johnsongrass will out compete alfalfa and bermudagrass for light and nutrients. A possible auto toxicity but I suspect it is more competition than chemical.
Ryegrass will effectively kill off bermudagrass, if it is allowed to persist into the summer growing season. Alleopathy or competition?
Established alfalfa is reputed to prevent germination of alfalfa seed, and I am sure there is this apparent effect in much of the nation, but seedling alfalfa has no problem thickening a stand, in this soil and climate. Now is an auto toxicity wrongfully blamed for killing off it's poor little babies? Are there other factors involved? Or is this a benifit of our hot dry summers? A coincidence rather than a cause?
Cover Crops:
If cover crops work for you, count it as a blessing. Here a cover crop is a rare bird seen only with irrigated ground, Let that read garden.
We simply do not have the moisture to grow both a cover crop and a cash crop.
HERE our pan evaporation is almost double our annual rainfall.
HERE evapo-transportation is 60 to 70% of the pan evaporation, giving us a loss of moisture needed by the corp.
HERE fallow ground has 30 to 40% of the moisture lost as pan evaporation. Our a summer fallow helps an establishing alfalfa stand survive the first season. A 12 or 15 month fallow period is even better.
The dirt farmer math is this.
Our dirt will hold 2" of moisture for each foot of depth. Six feet of soil will hold 24" of moisture. We get 36" of rain, on average. Two thirds of that is 24". Our average summer rainfall is maybe 10" but 5" is more realistic.
That is not adequate moisture to insure fall planted alfalfa will have 4 to 6 feet of root growth going into our summer drought.
Spring seeded alfalfa, HERE, has plant vigor problem which equates to a weed problem. | |
|
Alleopathy
