PARTICIPIAL PHRASE. Present participles, verbals ending in-ing, and past participles, verbals that end in-ed (for regular verbs) or other forms (for irregular verbs), are combined with complements and modifiers and become part of important phrasal structures.Participial phrases always act as adjectives.ometimes part of the noun phrase is delayed until the end of the sentence so that that portion of the phrase (usually modifying phrases  participial or prepositional) can receive end weight or focus.
Insect borers often attack trees that are weakened or damaged by other causes. In some cases, borers and plant pathogens are associated with the same canker. Leaf drop Leaf drop is generally caused by plant pathogens or environmental problems.
Some fungal and bacterial tree diseases cause prematurely falling leaves. These diseases, except for Dutch elm disease, are usually not lethal, but may weaken trees. Shade trees, ornamental trees and fruit trees may be infected with the same disease organism but display different symptoms.