Common ragweed is found throughout the United States, causing problems
in many crops. It is also the primary cause of hayfever for many allergy
sufferers. Ragweed is a robust, competitive weed, reaching over 8
feet in height. It posesses finely serrated leaves and grows upright
with moderate branching. There are two other weedy species of ragweed
– giant ragweed and lanceleaf ragweed, but these do not generally
cause problems in peanut crops.
YELLOW AND PURPLE NUTSEDGE
Yellow and Purple Nutsedge are perennial species that rank among
the most troublesome weeds throughout the world. These species can
be distinguished on the basis of leaves and tubers. Yellow nutsedge
is typically a large sprawling, pale green plant with leaves that
gradually taper at the tip. Purple nutsedge is a more compact, dark,
almost greasy-green plant with somewhat more blunt-tipped leaves.
Purple nutsedge tubers are dark, wiry, and connected in chains.
Tubers of yellow nutsedge are not connected from plant to plant.
||SICKLEPOD AND COFFEE SENNA
Sicklepod and Coffee Senna, both sometimes referred to as “coffee
weed,” are weedy cousins that look very similar just after emergence.
Seedlings of these species can be separated by the presence/absence
of hairs along the stem of the cotyledons. Sicklepod is hairless,
while coffee senna has numerous hairs where the cotyledons are attached
to the main stem. On larger plants, leaflets of sicklepod are rounded
while coffee senna leaflets are pointed. Seed pods of sicklepod curve
downward; seed pods of coffee senna curve upward. Of the two, sicklepod
is a more common pest in peanut fields.
Yellowtop, also known as golden crownbeard, is a summer annual broadleaf
weed that is commonly found in peanut fields in Texas and parts
of Oklahoma. It grows up to 3 feet tall with much-branched, grayish
Wild radish is thought to be a problem in winter crops such as small
grains and canola. However, wild radish has become an increasing problem
in peanuts in recent years. This plant forms a rosette of leaves that
look similar to mustard greens. The leaves have deeply indented lobes
and are covered with numerous stiff hairs. As the plant matures, pale
yellow flowers are produced on a seed-stalk that arises from the rosette.
Florida beggarweed is an annual broadleaf with trifoliate leaves.
It often attains heights well over 5 feet. The leaflets are lance-shaped
with a characteristic purple spot and numerous, small hairs that
give a velcro-like feel. The seeds are also covered with fine hairs
that readily stick to clothing and the fur of animals. Florida beggarweed
is one of the worst weeds in Southeastern peanuts.
Eclipta is an annual broadleaf pest considered to be a “wet
weather” weed in many parts of the Peanut Belt. Its narrow
leaves range from 1 to 5 inches in length and up to about an inch
wide. Eclipta produces a distinct white, round flower about half
the size of a dime. Plant growth habit is either upright or prostate.
In the prostrate or spreading form, eclipta commonly roots at nodes.
Common lambsquarters is a small seeded annual broadleaf species particularly
troublesome in the Virginia-Carolina region. It is an upright plant
which can exceed 7 feet at maturity. Its arrowhead-shaped leaves grow
alternate and often have a whitish dusty appearance on their undersides
even in the seedling stage.
Texas panicum is an aggressive, relatively large-seeded annual grass
that is common in much of the peanut acreage in the United States.
It has wide, almost-frizzy leaf blades and forms numerous tillers.
Its vigorous fibrous root system makes clean harvest of peanuts nearly
Spurred anoda is a troublesome broadleaf member of the Mallow or
Cotton family most common in the Virginia-Carolina area. Its alternate
toothed leaves are 2 to 4 inches long and sometimes have purplish
veins. It produces small, pale blue flowers and a unique fruit that
looks like a fancy ribbed pie surrounded by a star.
Wild poinsetta is an exotic weed pest spreading in many parts of
the Southeast. As a member of the Spurge Family, it has hollow stems
and milky, latex-like sap. In the cotyledon stage, it resembles
a weak, pale green cocklebur seedling. Mature plants can have numerous
leaf shapes even on a single specimen.
Hophornbeam copperleaf is a freely branching annual broadleaf weed
with finely serrated leaf edges. Copperleaf has bright green leaves
throughout most of the growing season, but these turn a characteristic
copper color as the plant reaches maturity in the fall. There is a
related species referred to as Virginia Copperleaf.
Palmer amaranth is an annual pigweed species that is becoming an
increasing problem in some areas. It can reach heights well over
6 feet and can be very difficult to control once established. Unlike
other pigweed species, Palmer amaranth has a long, slender seed
head and a more robust appearance.
Bristly starbur is an annual broadleaf weed common in much of the
Southeast. In addition to the accepted common name, it is also called
“goatspur” or “Texas sandspur.” It has rough
textured “fuzzy” leaves and an upright but profusely
branching growth habit. Its seed form with two sharp pointed prongs
that make the mature plant extremely “bristly.”
Pitted morningglory is one of several annual morningglory species
that occurs in peanuts. Its cotyledon leaves are deeply cleft and
pointed. Its heart-shaped true leaves lack hairs and frequently
have a purple margin. It produces small white flowers.
Prickly sida, also known as teaweed and ironweed, is an annual broadleaf
weed that becomes rather woody as it matures. It has serrated leaves
that range in size from 1 to 2 inches long and a third to two-thirds
of an inch wide. Prickly sida produces small pale yellow flowers on
a distinct stalk.
Redweed or chocolateweed is an annual broadleaf species that can
infest peanut fields. This weed possesses triangular-shaped leaves
with jagged margins. The younger stems may have a reddish color.
Redweed grows upright but may lean as the plant matures, exhibiting
a more semi-prostrate habit.
Florida pusley is a low growing, annual weedy species that appears
almost prostrate. It can be effectively controlled only with pre-plant
incorporated herbicides. Florida pusley has bright green leaves with
a distinctive recessed mid-vein. The stems are very hairy and may
have a purplish appearance. The flowers are white with six petals
in a star-shaped whorl.
Spider flower is also called Cleome or skunk weed and has a strong,
pungent odor. It is found in localized areas throughout the southeast
and can be a problem in peanut production. Spider flower will form
a cluster of leaves at the base, with three to five leaflets per
stem. It has a characteristic purple cast and will grow 2 to 3 feet
in height. Spider flower will produce white or yellow flowers and
long thin seed pods similar to that of wild radish or sicklepod.
Burgherkin is a member of the cucurbit family and is similar to many
cultivated melon-type species. The leaves are deeply serrated with
heavy pubescence (hairs). The fruit are 2-3 inches long, watermelon-shaped,
and covered with numerous soft prickles. Burgherkin vines may extend
6-10 feet from the rooting stem and cause severe problems with harvesting.
In addition, the fruit will be harvested with the peanuts causing
contamination and drying problems.
Tropic croton is an upright, branching annual broadleaf with serrated
leaves. Tropic croton has a rough hairy stem, but it is not as hairy
as the related species, wooly croton. Its gray-brown seed are a
desirable food for doves.
Tall morningglory can be found in many peanut fields. Similar to
other morningglory species, tall morningglory has a vining, prostrate
appearance that envelopes the peanut canopy. Tall morningglory possesses
heart-shaped leaves with over-lapping lobes at the base and slightly
SMALL FLOWER MORNINGGLORY
Small flower morningglory is probably the most common morningglory
species in the Southeast and can be a serious problem in peanut
production. In the cotyledon stage it resembles a wild radish seedling,
with heart-shaped cotyledons. As it grows, small flower morningglory
will stand nearly erect until 12 to 18 inches tall then begin to
run. It has heart or spear-shaped leaves and produces small blue
flowers in a head-like cluster.
Tropical spiderwort is an annual species similar to common dayflower.
It is distinguished from dayflower by the presence of subterranean
(underground) flowers. The leaves are spoon-shaped with parallel
venation and blue above-ground flowers. The stems are succulent,
and the plant re-roots quickly after cultivation. It spreads by
seeds and is becoming one of the most prevalent and troublesome
weeds in peanut production. Spiderwort germinates throughout the
season, hampering control efforts.