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Figs are grown by numerous homeowners,
particularly in the eastern part of the state. Generally, figs are relatively free
of disease. In most instances when diseases occur, they are associated with
soil-related problems or climatic conditions such as winter temperatures in the lower
teens or colder or extended rainy periods in the summer when fruit are ripening.
Nematodes
Root knot caused by the root-knot nematode is the major disease affecting figs grown in
sandy soil. Damage from this root-feeding nematode is progressive and results in
poor growth, low vigor, yellowing and bronzing of foliage, low yield and poor fruit
quality. To determine if root knot nematodes are causing the above ground symptoms,
examine the roots for galls. Your local county extension agent can assist you in
obtaining a diagnosis.
Control:
Currently there is no chemical registered for nematode control on established plants.
If the root-knot nematode commonly occurs in the area, or if a soil assay indicates
the nematode is present, some type of control procedure should be used prior to planting.
The following may aid in reducing nematode problems:
Choose a planting site in which a fig plant has not been previously grown,
or where root-knot susceptible plants such as tomatoes, okra, or tobacco
have not been recently grown.
Complete fallowing of the planting site (approximately 4 ft x 4 ft area)
during the summer and fall prior to planting can reduce nematode populations.
If only one or a few fig bushes are being planted, removal of the existing
soil and replacement with a high organic potting soil mix can be used.
Remove the existing soil from a 3 to 4 ft diameter area to a depth of
18 to 24 inches then fill the hole with soil potting mix that can be obtained
at most garden centers. High organic matter in the soil can reduce
root-knot nematodes.
Plant only nematode and disease-free plants.
None of these
practices will totally prevent reestablishment of root-knot nematodes but should
help the plant get off to a good start. Water and fertilize the plants to maintain
adequate but not excessive vigor.
Blights, Stem
Cankers, and Leaf Spots
Several fungi cause leaf and stem
blights, stem cankers and leaf spots. These can result in the wilting and dying of
stems, branches and leaves. Often the starting points for these diseases are areas
on twigs and branches that have been injured or killed by cold injury. Prune out and
dispose of all injured and dead twigs and branches. Rake up and dispose of all
fallen leaves.
Fruit Problems
Anthracnose
Anthracnose results in a soft rot and dropping of the fruit. The
first symptoms appear as small sunken and discolored areas. The areas increase in size and
pink masses of spores become visible. When immature fruit are infected, they may mummify
and remain on the branches in a dried condition. Fallen and diseased fruit should be
disposed. Dried and diseased fruit should be removed from the trees since these will
harbor the fungus.
Premature
Fruit Drop Sometimes the fruit fail to
mature. This may not be due to disease but rather to natural conditions
such as the type of plant and the kind of flower it produces. Figs may
bloom several times a year; the fruit that develops from early blossoms
may be injured by spring frosts while the fruit from late blossoms may
not have sufficient time to mature. Fruit may also drop from plants stressed
by nematodes or environmental conditions such as dry weather.
Souring
of Fruit "Souring" results from spoilage due to
fermentation by various yeasts, other fungi and bacteria. This condition is most severe
during prolonged rainy periods. Pick figs regularly and do not allow them to become over
ripe on the tree. If souring occurs, little can be done other than to remove and destroy
all infected fruit.
Cold Injury
Cold injury is often the limiting
factor particularly in the piedmont and mountains. Cold injury can be severe enough
to kill the plant or weaken it, making it more susceptible to twig and stem canker-causing
fungi. Buds on injured branches shrivel and fail to leaf-out. To aid in
reduction of cold injury, figs should be planted in a protected area and maintained in
good vigor but avoid the use of excess nitrogen. Killed and injured branches should
be pruned out in early spring.
Nutritional
Problems
Nutritional problems
can cause low vigor, small fruit, and poor fruit production. Prior to
planting, have a soil test done by the N.C. Department of Agriculture
to determine nutritional needs. Additional tests may be needed later if
symptoms of low vigor or poor fruit production are observed. Your county
agent can provide soil test information.
Other Links
Plant
Disease Information Notes Home Page
North
Carolina Insect Notes
For assistance with a
specific problem, contact your
local North Carolina Cooperative
Extension Service
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Caution:
The information and recommendations in these Notes were developed for
North Carolina conditions and may not apply in other areas.
Recommendations of specific chemicals are based upon information on the
manufacturer's label and performance in a limited number of trials. Because
environmental conditions and methods of application by growers may vary
widely, performance of the chemical will not always conform to the safety
and pest control standards indicated by experimental data. All recommendations
for pesticide use were legal at the time of publication, but the status
of registration and use patterns are subject to change by actions of state
and federal regulatory agencies. Last printed 04/91
Published
by North Carolina Cooperative Extension Service. Distributed in furtherance
of the Acts of Congress of May 8 and June 30, 1914. Employment
and program opportunities are offered to all people regardless of race,
color, national origin, sex, age, or disability. North Carolina State
University at Raleigh, North Carolina A&T State University, U.S. Department
of Agriculture, and local governments cooperating.
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