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Newcomers and visitors to Florida often remark on the coarseness of the local lawn
grass. They are referring usually to St. Augustinegrass, our main turf.
Despite its shortcomings,
susceptibility to drought and the chinch bug, St. Augustine performs very well in the
region. It is highly competitive against weeds, usually smothering them, and it does
well in diverse soils, under salt stress, and in moderate shade. The superior
adaptation of St. Augustinegrass extends to low maintenance situations, such as canal
embankments, where it generally performs better than bahiagrass, as long as there is a
source of moisture.
The widespread expansion of St.
Augustinegrass in Florida and other coastal areas is partly a function of the widespread
installation of fixed irrigation systems, and an efficient turf production industry.
Before the 1960's, many lawns were plugged rather than sodded, and bahiagrass had
been expanded as an escape from the chinch bug problem.
The Floratam variety of St.
Augustinegrass was released by the University of Florida and Texas A & M University,
in 1973, for its resistance to the chinch bug and SAD virus. In Texas, where the
virus was a problem, Floratam winter-killed too badly to be widely used, and was replaced
in the 1980's by Raleigh. In Florida, where the chinch bug was a more serious
problem, Floratam was eventually overcome by a virulent race chinch bugs.
Nevertheless, Floratam has excellent tolerance to the herbicide atrazine, the main pre-
and postemergent herbicide used in St. Augustinegrass, and it has aggressive stolons
(above-ground runners) that can grow laterally at 3/4 inch per day.
St. Augustinegrass winterkills
when temperatures reach 16 to 20 degrees Fahrenheit (-9 to -7 degrees Celsius). New
dwarf varieties have been released since 1975 with lower growth habit, and better shade
and cold tolerance than Floratam. While none has yet captured a major niche,
Seville, Delmar, and Palmetto are examples of good performing dwarf St. Augustines.
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