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Grasses and the Problem is the Solution
publication date: Jan 5, 2010
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author/source: Doniga Markegard
 Grass and the Principle of The Problem is the OpportunityThis month we will focus on grass as our featured species. We will take a look at backyard lawns and larger acreage covered in grass and how to turn a resource-draining problem into a resource-gaining solution, all powered by the sun! In the United States, grasslands cover 36.7% or 336 million hectares (Mha) of land. This is compared to 157 Mha or 17.1% of land in cropland. Grasses make up several food plants such as bamboo, wheat, bananas and rice. Grasses are excellent when mixed with legumes for a cover crop to add nutrients to the soil as well as create a pasture mix for animals. Grasses, or more technically graminoids, are monocotyledonous, usually herbaceous plants with narrow leaves growing from the base.  monocot (left) dicot (right) They include the "true grasses," of the Poaceae (or Gramineae) family, as well as the sedges (Cyperaceae) and the rushes (Juncaceae). We will be talking this month about the Poaceae family and which species in particular you may be looking at utilizing in your permaculture landscape whether it be for a food source, a soil builder or to hold in the soil.  Typically when I am working in a backyard setting and I do
an initial site visit and find a lawn taking up the majority of the property, I
will suggest that the lawn be sheet mulched and turned into an edible landscape
for the landowner. This is not the
case when I do a consultation for a property that has more than an acre or two
of lawn. In this case, depending
on the landowner's goals, I suggest they stop mowing, mix in some diverse
forage species, amend the soil, put in cross fencing for pasture rotation and
bring in some animals. Lawns are a
big problem and do not fit into a permaculture system. They typically use way more energy to
maintain than they produce. Inputs
include excess fertilizer and water to keep them green, fossil fuels to keep
them short and poison or traps to keep the borrowing mammals out. Lawns provide very little outputs. How can we turn this into a
solution? In the sheet mulching example I gave, by using a biodegradable layering system on top of your lawn, such as cardboard to block out sunlight so the plants beneath die, horse manure from the stable down the road and woodchips from the waste of the tree company, you now create a giant compost pile full of fertility where your lawn once was with very little input. The green of the lawn decomposes and turns into nitrogen fertilizer. Now you have the ideal environment for growing fruit trees, edible and useful plants. Chickens also love to scratch in the stable waste and woodchips you bring in since they are typically full of grubs and insects for them to feast on. You turn waste into food. For more on sheet mulching visit EarthActionMentor Articles: Sheet Mulching: Turning Waste into Resource and Turn your backyard into an edible oasis! In the pasture example I gave, you are implementing a solution to a much bigger problem in the scheme of the carbon cycle. To put it simply, grasses evolved with animals grazing them and there is a lot going on under the soil when grasses are grazed in a way that allows ample regrowth time in between periods of grazing. In Gaia's Garden, Toby Henenway describes roots as "nature's subterranean humus builders...roots add organic matter in vast quantities during their constant cycles of growth and decay." Grasses' roots are some of the most efficient at doing this job. When the grasses are grazed, the roots die back adding carbon to the soil. To look towards nature, native herds traveled in tight groups and had predators to keep them moving so as never to overgraze, but to graze in a pattern that speeds up the productivity of perennial grasses, keeps diverse grasslands open and encourages seed germination. Recent research indicates that the productivity of grassland managed with appropriate timing and herd movement can sequester carbon at a rate that has the potential to stop global warming in 15 years or less by utilizing the productivity of grassland ecosystems as the highest contributor to carbon sequestration. This type of management on our grassland ecosystem ultimately builds soil. A 0.5% increase in soil organic matter on 75% of the world's rangelands, which is roughly 11.25 billion acres, would sequester 150 gigatons of atmospheric carbon, which would result in the solution to the climate change crisis we are facing. As a species, we need to shift from carbon-releasing agriculture to carbon-sequestering agriculture. So, if there is an opportunity to turn acreage into productive pasture, here is a solution on a large level. To read more on this, check out these articles: Moving Our World Towards Sustainability by Allan Savory and Christopher Peck or An Inconvenient Cow by Matthew J. Rales Grasses for Food Bamboos Bamboo is my favorite grass to grow as food as well as for its many other uses. There are two main groups of Bamboos-Nastus spp. or Clumping Bamboos and Phyllostachys spp. and other genera or Running Bamboos. Both types produce edible shoots. Bamboo shoots are consumed all over the world. Crisp in texture, they typically take on the flavor of the food they are cooked with, although there are certain varieties that have a sweetness all their own. The shoots are best harvested just as they emerge from the soil. The shoots are cut from the main rhizome.  Bamboo Shoots Bamboos are a
very rewarding grass to grow. They
make a great screen, can be used as they get larger for plant supports and
building, and provide a tasty treat in soups and stir-fry. For more information on bamboos visit: American Bamboo Society There are several species of grasses used as cover crops to build soil and hold soil in place to prevent runoff. Cover crops are planted to build and hold soil as well as smother weeds. Plant your grass cover crop with a legume such as clover or vetch to get the best results for soil building or animal fodder. Cover crops range from long-term perennials such as red fescue, Festuca rubra, and Dutch white clover, Trifolium fragiferum,   Red Fescue Dutch white clover to short-term green manures to be slashed, lightly tilled or grazed such as annual ryegrass, Lolium multiforum, and common vetch, Vicia villosa. Cover crops provide a barrier over the soil to keep the soil moist, prevent soil runoff and build leaf litter on top of the soil. The roots of grasses go deep into the soil to loosen the earth and draw in nutrients to make them available for plants. The roots are doing their job to add organic matter to the soil in their constant process of growth and decay.  Root systems of prairie plants Planting a cover crop
is often much more efficient than sheet mulching, especially when done on a
large scale. Sheet mulching can be
labor intensive; cover cropping can provide similar results while letting the plants
do the work. This process is
sped up if you have grazing animals such as sheep or cattle rotating through
your cover crops or perennial pastures.
After the sheep or cattle have grazed it down, you can bring your chicken tractor through to take advantage of the grubs and insects from the
manure piles the animals have left behind. The animals will add additional fertility by leaving their
droppings as fertilizer. When this
system is working effectively, the permaculture system is requiring very little
inputs. The animals are happy to
be on fresh pasture, the soil and the plants are growing rapidly and the humans
are sitting back and enjoying watching a system powered by the sun. |