Back to the chufa discussion earlier on this thread - I found this on the NWTF site:
http://www.nwtf.org/online_chats/online_chat_7-1-10.html>>>Q: In Washington, we need more solid evidence to prove to the government that chufa nutsedge is different than yellow nutsedge. They are different subspecies, but they get lumped into the same category out here. With the info I have above, I'd like to know the scientific name or variety of chufa. In Washington and other states Cyperus esculentus eptostachyus is an introduced yellow nutsedge and in the South Cyperus esculentus macrostachyus is a native variety. Is chufa a cultivated genotype of the native or the non-native? I want to plant chufa for wild turkeys but I hit roadblocks with agencies that consider chufa a noxious weed.
— Eric Braaten, Electric City, Wash.
A: There are a number of references in scientific literature and on the Internet to yellow nutsedge and its relationship to chufa. Both are the same species but they are very different variants. Generally, most authorities agree that the weedy, invasive type (yellow nutsedge) is Cyperus esculentus var. esculentus, and the cultivated, non-invasive variety (chufa) is Cyperus esculentus var. sativus.
Research by Dr. Andrew Dyer at the University of South Carolina (Aiken branch) has shown that the two variants are quite different in physiology and reproductive capability. Nutsedge produces a widespread network of tubers and roots and chufa produces a compact ball of tubers directly under the center of the leaves. Nutsedge flowers early in the summer, and chufa, if it flowers at all, does so in late summer or early fall. This means the likelihood of hybridization is near zero.
Dyer has suggested that the two variants are so different that they may deserve distinct species status. Nutsedge is also invasive, spreading quickly if introduced. Chufa will not spread from a planting site, and in fact, since it does not compete well with other vegetation, will quickly die out if not maintained.<<<
Maybe this is the reason that I'm killing chufas with herbicides that have no effect on yellow nutsedge.
I also found this on another page:
http://www.nwtf.org/online_chats/online_chat_7-9-09.html>>>Q: I've planted my chufa and it appears to be coming up well, but a lot of grass and some broadleaf weeds are coming up with the chufa. Should I be worried about this and what can I do about it?
A: You definitely don't want weed competition in your chufa plot if you can help it. For grass competition, use 1.5 to 2 pints of Poast herbicide per acre (see the herbicide label for non-cropland use) along with one quart per 100 gallons of solution of crop oil concentrate as a surfactant. Surfactants are wetting agents that lower the surface tension of a liquid to allow easier spreading and lower the interfacial tension between two liquids. If you also have broadleaf weeds such as coffee weed and pigweed, use 1.5 pints per acre of 2,4-DB (also called Butyrac 175), but do not use 2,4-D because it may kill the chufa. You may use this mixture alone or in a tank mixed with the Poast. In either case, use the same rate of crop oil concentrate as recommended for the Poast mixture.<<<
Notice that he specified NOT to use 2,4-D because it can kill the chufa, which is exactly what I've experienced. And yet a recent article in the NWTF magazine recommended a quart of 2,4-D per acre. Sure wish 007 could get a big grant to figure all this out.
