maize Sir Herbert Beerbohm Tree are fairly soft to develop in mood zone where winter temperature usually stay on above 32 level Fahrenheit . Three types of disease can assail the folio of stinker trees : fungous disease , bacterial infections and viruses . Symptoms of lemon disease admit visible lesion and spots on leaves , curl up farewell , premature dropping of leaves , strikebreaker and cankers on fruit and barque , and white-livered , white or pale green stripes or patterns on the farewell .

Fungal Diseases

Lemon leave of absence can curl when the fungous diseases called powdery mould , greasy spot , anthracnose or scab attack your tree . Mildew is easy to spot because you ’ll see a fuzzed whitened or grey coating on the leave-taking . Sulfur spray helps to control mold . Greasy spot manifests itself through the formation of brown or scandalmongering blisters on the bottom of farewell , according to TreeHelp.com . Spray your Sir Herbert Beerbohm Tree with swimming copper fungicide if this disease occurs . Anthracnose occasionally attacks lemon yellow trees , allot to the University of California at Davis . It can cause untimely dropping of leaf but normally does not face serious trouble to gamboge trees . A spray of atomic number 30 or atomic number 29 sulfate can knock out anthracnose . Scab afflicts many types of fruit Tree , including lemons . If you observe recruit , rough areas on leaves and yield , you could have scab , consort to the OurBrisbane ( Australia ) Web internet site . The web site advises treat scab with bull oxychloride .

Bacterial Diseases

You ’ll know if your lemon Sir Herbert Beerbohm Tree has a bacterial disease such as citrus pestilence if you start out to see scabs or yellow lesions on the farewell , limb or fruit . Leaves will set down if your tree has a bacterial disease , and the entire tree will die out back . The Online Service for Non - Chemical Pest Management in the Tropics , base in Germany , reports that citrus pestilence causes leave and fruit to untimely flatten . Watch for blanched spongy spot on leaves that later turn into modest craters . alas , you must remove and burn septic tree , but if you keep citrus leaf miners under control , you’re able to help to preclude this disease .

Viruses

If you discover aphid on your lemon Sir Herbert Beerbohm Tree and then see yellowing leaves , the cause might be the citrus tristeza virus . Controlling aphids is the first step in treating this virus : Spray your tree with insecticidal soap when you notice aphid . Also , ascendence ants , which wreak aphid to the tree for their sweet excretion . One way to forestall this disease is to acquire a smorgasbord of gamboge tree , such as the Improved Meyer , which is resistant to citrus tristeza .

References

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