Trumpetvine (Campsis)
Plant Health Problems
Diseases caused by Fungi:
Leaf spots, Cercospora, Phyllosticta.
These diseases are recognized as spots of dead tissue scattered over the
leaf surface. Most have distinct margins but the size, shape, and color can
vary. Several fungi cause leaf spots although they are usually not serious
except during periods of extended leaf wetness and humidity. Some defoliation
can occur when infection is heavy.
Leaf spots can be managed by raking and removing fallen leaves to eliminate the
source of overwintering inoculum and by maximizing plant vigor by following
good cultural practices. Although usually not necessary, control can also be
achieved with the use of fungicide sprays applied when new growth emerges in
the spring. Several applications may be necessary, especially when wet weather
persists. Among the compounds registered for use in Connecticut are
chlorothalonil and thiophanate-methyl. Consult the label for dosage rates and safety precautions.
Powdery mildew, Erysiphe, Microsphaera.
White powdery spots or patches develop on the leaves, usually during mid-
to late summer. Leaves are usually not obviously curled or deformed and
although some defoliation can occur, this disease is not considered a serious
problem.
Disease can be minimized by carefully picking off affected leaves as soon as
symptoms are evident and by raking and removing fallen leaves to reduce the
amount of overwintering inoculum. This disease is generally not serious enough
to warrant chemical control although fungicide sprays can be applied as soon as
symptoms are visible. Among the compounds registered for use in Connecticut are
potassium bicarbonate, thiophanate methyl, and sulfur. Consult the label for dosage rates and
safety precautions.
Insect Problems:
Planthoppers, Metcalfa pruinosa and Anormensis
septentrionalis.
These sucking insects damage plants as adults and nymphs. The green nymphs do
not do much damage but cover themselves with white cottony strands, which makes
them very noticeable. Grayish-black, 1/4 to 1/3" (6-8 mm) long females lay
eggs singly inside twigs of host plants where they overwinter. In the spring,
after hatching, the nymphs feed on developing leaves and shoots. Control is
seldom necessary.
Scale.
Occasionally, the olive parlatoria scale infests trumpetvine. If control is
needed, ultrafine horticultural oil can be applied in late winter or during the
growing season; malathion can also be applied during the growing season. Both
products are registered for use against this pest in Connecticut. Consult the
label for dosage rates and safety precautions.
Whitefly.
If conditions are right, whitefly may become a problem on trumpetvine. The
greenhouse whitefly,Trialeurodes vaporariorum, the sweetpotato whitefly,
Bemisia tabaci, and silverleaf whitefly, Bemisia argentifolii,
commonly infest many kinds of greenhouse-grown plants, which subsequently are
often carried into the field where they may persist. The life cycles of these
species are similar. The tiny, white moth-like adult has a mealy appearance due
to the small particles of wax that it secretes. It lays groups of eggs on the
underside of leaves. The eggs hatch into small oval crawlers, which then settle
down on the undersides of leaves and become scale-like. These insects spend
about 4 days in an immobile pupal stage before becoming adults. About 5 weeks
are required to complete the life cycle in the greenhouse. Insecticidal soap or
ultra-fine horticultural oil, which are among the compounds registered for
control of this pest in Connecticut, sprayed on the undersides of leaves, can
be used against whiteflies in the greenhouse or the field. Azadiractin (neem),
also directed to the undersides of the leaves, can also be used. Repeat
applications of sprays will probably be needed because some stages in the life
cycle are dormant and not affected by insecticides or other sprays. Chemical
control using conventional insecticides is difficult because of widespread
insecticide resistance. Season-long control can be achieved with imidacloprid
applied as a systemic taken up by the roots. Consult the label for dosage rates
and safety precautions.