A N EVICTION NOTICE
Poo Annua on Fairways
by LEON V. ST. PIERRE, Superintendent, Longmeadow Country Club, Longmeadow, Mass.
(Editor's note: This article deals with the
control of Poa annua on fairways—the archenemy
of northern golf course grasses. Several new pre-
emergence materials are now being manufac
tured for Poa annua control, such as bensulide,
and tri-calcium arsenate. Experiment station re
sults have been variable for the most part, and
course superintendents have been
hesitant to do much on their courses. More
recently it seems that changes in application
techniques worked out by practical superinten
dents are proving successful with one of these
pre-emergence materials, tri-calcium arsenate.
T r i o lei urn arsenate is now being successfully
light rates more frequently, rather
than one ful l application of toxicant at one time.
Such a success story is being reported here.
However, we caution that if you are interested,
you first test this material on a small scale
because your conditions will not be the same as
Nursing Poa annua during the summer months
of each year is the least gratifying job that
comes my way. After years of worry and heart
breaking experience with Poa, we decided to give
the pre-emergence herbicides a try on our fair
ways. We chose 48 per cent tri-calcium arsenate
and made the first application on May 11, 1967,
at the rate of two pounds per 1,000 square feet.
A second treatment was applied June 8, 1967, at
one pound per 1,000 square feet. This provided
approximately 1.5 pounds actual toxicant per
1,000 square feet. We noticed no thinning of
the Poa annua until July 18, when i t started to
A close look at No. 7 fairway. Note the solid rows of bentgrass coming through with virtually
from Poa annua, an excellent
During the first week of August, all
were sprayed for broad leaf weeds, including knot-
weed, with a combination of 16 pounds Dicamba