Saturday, December 22, 2012

december grasses II

"there is mounting evidence that these [perennial] systems can produce certain ecological services more efficiently and effectively than agroecosystems based on annual crops. examples include (i) soil and nitrogen loss rates from perennial crops are less than 5% of those of annual crops; (ii) perennial cropping systems have greater capacity to sequester greenhouse gasses than annual systems; (iii)in certain scenarios, some perennial crops appear more resilient to climate change than annuals, e.g., increases of 3 to 8 degrees centigrade are predicted to increase north american yields of the perennial crop switchgrass..." n.g.jordan. n, boody,w. broussard, et al, "sustainable development of the agricultural bioeconomy." science 316(2007):1570-1571._______________________________________ all ecosystems are a mix of annuals and perennials and so is the garden...with the brussels sprouts just about out of time ( i think...haven't taken them out yet ) the garden's population is returning to perennials...they have been the focus of the project since the beginning and will be even more so next season ( although there will be maize and [hopefully] annual teosinte ) with the wheat grass from kansas taking center stage...that particular grass is at the heart of a dormancy conflict that is raging out there...the zea diploperennis has been long dormant as well as the chinese yams...the eastern gamagrass is still holding out today with chlorophyll discernible in quite a few leaves and the wheat grass from kansas and the forage variety i planted a couple of seasons ago are both still up and running...winter has finally arrived...but it arrived in a strange form last year as well and my winter wheat ( admittedly an annual ) never did go dormant...which may explain why i was finding seed heads in april last year, about a month ahead of i have to wonder if the wheat grass from the land institute will follow the same pattern and grow all winter ( the wheat grass in my back yard is till running as well )...all we can do is watch...certainly the early march warmth, coupled with a cool off and the subsequent drought, confused the perennials...especially the jerusalem artichokes which delivered a disappointing harvest compared to previous years...that will become a large part of the focus of my backyard...i have peopled it with as many native perennial species as i could lay my hands on for the space i have to monitor how they react to next season's weather...if the climate is changing ( and we are now a part of hardiness zone six instead of five ) then what better way to monitor its impact than by observing native species' reactions to it? well...there may be better ways but this is the best my limited brain can come up with and it gets me out into the fresh air most days...if the perennials can help ameliorate the impact of greenhouse gasses by sequestering more carbon in their roots as well as provide some subsistence then it's worth the effort.

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