These pests are also found on Strelitzia, Camellia and Yucca species. The leaf forms yellowish to brown spots that are contained by the veins but merge eventually turning the entire leaf brown then dieing. These may be found on surrounding weeds. Infected leaves die and fall from the plant. ) They are dispersed by infected plant cuttings or soil and travel along a film of water on the outside of the plant. Cordyline and Dracaena species may be infected by the leaf spot (Phyllosticta maculicola) which forms small brownish spots that have yellowish margins and has black fruiting bodies that forms coils of spores. Flowers fail to open, stems may grow sideways and the plant becomes stunted, dieing prematurely. This infection may also occur on the stems, and flowers may form abnormally or brown off and die. One generation occurs from three to eight weeks and is dependant on the current weather. which forms round black spots that have yellow margins. All Rights Reserved. Psidium guajava (Guava) is infected by (Glomerella cingulate). Chinese Wax Scale (Ceroplastes sinensis) is a domed wax scale that has dark spots around its margin and immature scales form waxy material around there margins. They can be found throughout the year on dead tissue and on live material during under ideal climatic conditions. Damaged areas such as a tear in a leaf or an opening made by an insect are more likely to be infected. In trees and shrubs it is difficult to control and generally not necessary, but in perennials and annuals control may be necessary in order to save the plant. It is difficult to control with out the application of chemicals, though strong jets of water greatly disturb the colonies. Species plants are native to tropical areas from Polynesia and Hawaii west to Southeast Asia, Australia, and Madagascar. Spiraea species are attacked by the fungal leaf spot (Cylindrosporium filipendulae). Asplenium nidus (Bird's Nest Fern) is an evergreen fern forming a remarkable rosette of broadly lance-shaped, glossy, bright green fronds adorned with contrasting dark midribs and wavy margins. Related Plants 'Chrissy' 'Fimbriatum' Agave species are susceptible to several types of scale including (Aspidiotus nerii), (Aonidiella aurantii) and (Pinnaspis strachani), but generally do not require control. Ladybeetle larvae and adults, parasitic wasps and predatory caterpillars normally control the scale. Winter Fusarium Leaf Disease in Turf Grasses can be minimised by aerating the soil, reducing thatch and avoid excessive nitrogen in the soil. Adult
Circular or angular dark spots appear on the leaves and are surrounded by necrotic areas that are yellowish. It is most prevalent during warm humid periods in soil with a high nitrogen level. The adult female has a circular or oval covering depending on the species and is up to 8mm across.