Foxtail in Title
Only – Carolina
Glenn Nice, Weed Diagnostician,
Department of Botany & Plant Pathology, Purdue University
When the tail of foxtail is spoken of in Indiana,
it is generally about the summer annual grasses, green, yellow,
and the ever popular giant foxtails that is referred to. However,
in reality the term foxtail is simply part of the common name
game, a name tagged to several plants. A quick search using
the word ‘foxtail’ on
plant database and you
get approximately 40 common names using the word “foxtail” covering
several genera ranging from a pine tree to several grasses.
Last spring we received several calls regarding
Carolina foxtail (Alopecurus carolinianus Walt.).
This foxtail, unlike the green, yellow and giant is a cool season
native grass that will produce seed in the spring and early summer.
Its distinguishing characteristic is its timothy-like seed head
(figure 1). Many spikelets are crowded into a soft spike. Each
spikelet has one flower. Although the seed spike looks like
a tiny timothy, with closer inspection with a hand lens, one can
see a small awn emerging from one side of the scale, timothy scales
do not have this. Carolina foxtail is a short stature
grass generally about 4 to 6 inches tall1. It
has a small membranous ligule, something else that distinguishes
it from green, yellow and giant foxtails. Leaves are 2 to 5 inches
long and 0.03 to 0.2 inches wide.
For the most part, Carolina foxtail is not difficult
to control. Research
from Purdue reported Glyphosate (Roundup Weathermax, Touchdown,
Glyphomax, etc) provided excellent control of Carolina foxtail
(98%) when applied in the fall2. Although no benefit
to the control of grasses, the addition of 2,4-D can be added to
reduce selection pressure of glyphosate resistant marestail (horseweed).
Canopy EX also provided excellent control (99%) of Carolina foxtail.
Research done in Southern Illinois reported fall application of
Basis and simazine controlled Carolina foxtail 100 and 96%, respectively3.
Be aware that some herbicides applied in the fall have rotation
restrictions that limit what can be planted the following year.
For the most part Carolina foxtail finishes its
life cycle once the hot dry months of summer arrive; however, I
have seen it in late June in Tippecanoe County. Mostly forgotten
about in late summer, the best time to control Carolina foxtail
is in the fall or early spring.
Figure 1. Carolina foxtail seed head. Robert
H. Mohlenbrock. USDA SCS. 1989. Midwest wetland flora: Field office
illustrated guide to plant species. Midwest National Technical
Center, Lincoln, NE. Courtesy of USDA NRCS Wetland Science Institute.
Figure 2. Carolina foxtail spikelet scale. Steve
Hurst. Provided by ARS Systematic Botany and Mycology Laboratory.
Peoria Heights, IL.
1Kansas Grasses, Kansas State University. Accessed Oct.
23, 2006. (http://spuds.agron.ksu.edu/digikey.htm).
22006 Annual Research Report. Bill Johnson, Purdue University
3Winter Annual Weed Control
with Fall-Applied Corn (Zea mays)
Herbicides. R.F. Krausz, B.G. Young, and J.L. Matthews. Weed
Technology: Vol. 17, No. 3, pp. 516-520.