Does anyone have any idea how much leaf weight can be harvested per acre per year if proper pollarding procedure is used? Assume dense forest in Missouri, 36" annual rainfall.
It depends on species and age of the tree. Here are a few figures:"Massey University research found that 5-10 year-oldtrees yield up to 22 kg DM per tree of edible forage,and that poplars and willows were similar in nutritivevalue. Condensed tannin levels are usually higher inwillows.Willow leaves are also high in zinc and magnesium,which are important animal health minerals. Howeversodium (salt) levels can be low in willow leaves, and,if little or no pasture is on offer, a salt block should beprovided. The tree bark also had good nutritive value.Willows produce more fodder than poplars, growing4-5 times the number of new shoots and carrying moreedible material, i.e. leaves, small stems and bark.Research trials by Massey University showed improvedlambing percentage for stock fed on poplar and willowforage compared with stock fed on droughts pasturealone.Mature poplars and willows shed a large quantity ofleaves in autumn and early winter. Once trees areabout five years of age, leaf fall can provide 60 kg ormore of dry matter per tree.
It is estimated that 1,000 bundles of leaf hay were neededper cow over a 6 month period. A bundle is of similar sizeto a sheaf of corn. One person should be able to cut anaverage of 30 bundles of fresh twigs and leaves per day.With practice this can increase to about 100 bundles perday. If an ash tree is cut once every four years (as happensin parts of southern Austria) an annual yield of between 20and 25 bundles can be expected. Nutritionally this is theequivalent of about 10 pounds of good meadow hay withthe added benefits of a higher mineral content.
"The sugar pod group, the mesquites, the honey locusts, carobs, and the sugary tips of such trees as striped maple, will help cattle take advantage of the dry perennial grasses. In a winter climate, the demand is really for carbohydrate fuels. So you design oaks and chestnuts. What you then find, to your surprise, is that this is the way it works. You don't have to design it in. God did that. Cattle grew up to take advantage of what was actually seasonal.There are plants like Tagasaste and Coprosma--evergreen and highly nutritious plants that go all year. Even though you let the cattle browse them, while they don't respond as fast over winter as they do in other seasons, they still regrow again.So you have three strategies, then, with these cattle and deer and goats and sheep.1: instead of just relying on annual pastures, have areas of permanent, high-mineral mobilization herbs throughout all your pastures-- dandelion, chicory, comfrey.2: Have evergreens, standing, high-nutrition tree crop within forage range that the cattle will coppice.3: Have high-sugar summer pods that will carry cattle through the semi-arid seasons. This group is critically important to range capacity.4: Also, you must have a winter high carbohydrate source--large nuts and acorns.These are the truly perennial components--the fruit of trees that stand in pasture."