fremmel

Has anyone tried using cover crops in newly planted rubber fields? Around here, in Udon, people seem to either intercrop with cassava or just plow the weeds in when they get too tall. That's all the rubber research station in Nong Khai knows about too.

We have a small 14 rai field that we planted this year. The soil is fine sand with a little clay and not much organic matter. The field also has a 1 to 2% slope. I'd like to try a cover crop to increase the soil fertility with organic matter and nitrogen fixing, crowd out the weed growth, and cut down on erosion.

I'm having trouble finding much information that's specific to rubber fields in Issan. Everything I've found on this forum and the Organic Farming forum is about using cover crops to prepare for field crops rather than intercropping with rubber. From googling it seems that cover crops are common in rubber plantations but everything is about southern Thailand, Malaysia, India, etc. Places that have climates and soils that are different from here. I have found a couple of references to academic studies in Isaan, here  and a good one here , There seemed to be some good results but also possibly problems with resource competion between the cover crop and the rubber during the dry season and/or with acidification of the soil.

What would be nice to find is a perennial that's been used here that I can plant and maybe cut back now and again when it gets too tall. Even an annual would be better than just weeds. In the meantime, it's about time to plow the weeds in and what I thought to do after plowing was sow sunn hemp, let it grow for a couple of months, and then cut it back or plow it in. I've not found anyone that talks about sunn hemp with rubber but i'm guessing it would be beneficial.

So, what I'm hoping for is any actual, real world experience with this or some advice from people with more farming experience than I - which is just about everyone.