The forsythia bush ( Forsythia x intermedia ) is an early forerunner of spring , with its cherry lily-livered blooms often peeking through the last of the Baron Snow of Leicester in northerly gardens . These large , fast - growing shrubs are light to grow . They require only full sun , well - drain grime and occasional pruning to keep them happy . While some gardeners may say it ’s impossible to damage a forsythia , some pests can afflict even these toughest of landscape shrubs .

Aphids

aphid are a common , but rarely fateful , job for young forsythia . These bug have soft , pear - shaped bodies that can be brown , gray , yellow , black , fleeceable or red . Aphids clump on the bottoms of untried leave of absence , unopened flower buds and young stems . They leave behind their waste , called honeydew , a clear liquid that can coat the shrub and lead to the development of sooty molding . If the aphid population on your forsythia is not out of ascendance , the University of Minnesota Extension recommends allow the bugs ' natural foeman , such as epenthetic white Anglo-Saxon Protestant , ladybugs and green lacewing fly , control them . You also can hear spraying your shrub with high - pressure level water system from the hosiery .

Plant Bugs

The fourlined flora glitch ( Poecilocapsus lineatus ) and the tarnished plant bug ( Lygus lineolaris ) lay eggs in the forsythia ’s balmy stems . The youthful bugs hatch in mid - May and lactate the sap out of the bush ’s tender leafage . Symptoms let in sunken areas around the puncture yap that pop out as transparent roach and become circular holes . The yellow - green fourlined industrial plant hemipteron has four mordant stripes alternating with three green stripes on its wing . The back of the mottled - dark-brown tarnished flora bug has a lily-livered yttrium pattern . To get rid of the pests , the Connecticut Agricultural Experiment Station recommend spraying with azadirachtin , malathion , ultrafine horticultural oil or insecticidal soap .

Two-Banded Japanese Weevil

The two - banded Nipponese weevil ( Callirhopalus bifasciatus ) eat the forsythia ’s leaf margins ( boundary ) , leave behind crescent - shaped notches . The weevil , which comes in varying sunglasses of brown , has faint white lines on its extension covers and whitish touch on its rear . The Connecticut Agricultural Experiment Station recommends spray with acephate in other August only if you see many of the adults and your forsythia is sternly damage .

References

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