AFM 91-19 / TM 5-629 / NAVFAC MO-314
24 May 1989
5-8. Step-by-Step Procedures. For best results,
f. Avoid high temperatures during or follow-
PGRs must be used correctly.
ing PGR application, if possible. They will cause
an increase in discoloration, and possibly thin-
a. MOW turf to the desired height 24 to 48
ning, of the turf grass.
hours before PGR application.
g. Apply PGRs with a tractor-pulled, multi-
b. Apply PGRs to healthy, actively growing
nozzle, boom sprayer for best results. Spraying
turf in the spring, about 2 weeks before seed-
slopes and bunkers with a hand-held, single-
nozzle boom often results in excessive or inade-
c. Use the correct dosage and apply uniformly
quate amounts of PGR being applied.
in 40 to 80 gallons of water per acre. Avoid
h. Do not apply PGRs to heat or drought
runoff, skips, and overlaps.
d. Delay spraying if clippings or other debris
i. Do not apply PGRs to scalped turf.
are present, as they will prevent uniform distri-
j. Mow PGR treated turf 10 to 14 days after
bution of the PGR.
e. Apply when rain is not expected for 4 to 8
k. Do not scalp PGR-treated turf.
hours and irrigation will not be provided for 8
hours. Amidochlor and flurprimidol, however,
5-9. Diagnosing Common Problems. The most
should be watered-in to improve their effective-
common problems associated with using PGRs
may be diagnosed using the following chart:
a. Poor growth suppression or poor seedhead suppression
(1) insufficient PGR applied, poor calibra-
(2) Turf mowed too close before PGR appli-
(3) PGR applied to dormant, partially dor-
mant, or drought-stressed turf.
(4) Rain or irrigation too soon after PGR
(5) Turf mowed too soon after PGR appli-
(6) Germination of grass or broadleaf weed
seed following PGR application.
(7) PGR applied too late, after seedheads
developed and began to emerge.
(1) Higher than recommended rate applied.
b. Abnormal discoloration
(2) Overlapping of nozzles or spray boom.
(3) Applied to sensitive species.
(4) Turf mowed too close before applica-
(5) Turf mowed with dull mower blade be-
fore or after application.