Growing Sod with Manure
Teams Two Texas Commodities
Fertilizers such as phosphorus, which may
run off into streams and rivers, continue
to raise environmental concerns. Texas researchers
are promoting a crop that can, literally,
take phosphorus away from livestock operations.
SARE-funded Texas A&M University researchers
grew high-end sod with manure on two large
dairy operations and, when they harvested
it, removed the phosphorus from the area.
Growing sod with dairy manure both reduced
phosphorus loads and potential runoff from
the dairies—up to 77 percent of applied
phosphorus was removed in a sod harvest—and
eliminated phosphorus fertilizer inputs used
to grow conventional sod. Since manured fields,
particularly when located near streams, create
a phosphorus run-off hazard, “we hatched
the idea that we could capture more nutrients
with sod than any other crop,” said
principal investigator Don Vietor of Texas
A&M.
Vietor and his collaborators grew recent
releases of warm-season and cool-season perennial
grasses—high-end sod prized by developers—established
in soil topped with raw manure or composted
manure, which reduced odor concerns. They
also seeded lower-end “sports” turf
on sloping soils to study phosphorus runoff.
The benefits were clear: They captured much
of the phosphorus that would otherwise run
off or leach from manure in a value-added
product—a far more profitable alternative
than hauling manure. When the sod was replanted
or used in commercial settings, phosphorus
run-off was reduced 9 percent compared to
sod grown with commercial fertilizer. Moreover,
manure improves water infiltration during
turf establishment.
Using an economic model, collaborator Darrell
Bosch at Virginia Tech estimated that a dairy
farmer who used manure to grow 50 acres of
sod could earn an additional $46,000 per
year. That new profit was based on returns
from sod minus the cost of buying corn silage,
a new input for the farmer who took 50 acres
of silage out of production to raise sod.
Vietor publicized the sod/dairy project
at Texas grower meetings and will also reach
out to extension educators. One dairy operator
who collaborated on the project has already
adopted the new crop, growing sod on part
of the waste field for his large-scale replacement
dairy heifer operation.
Vietor hopes that sod producers will consider
forming partnerships with dairy farmers. “Sod
producers now haul high-end sod to Dallas
from as far as the Texas Gulf Coast,” he
said. “Central Texas is a lot closer
to Dallas. As sod producers look for new
land, we’re encouraging them to look
in these areas where dairies are concentrated.”
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