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.
A close examination of leaves on the ground will likely show leaves with only a small portion of their stems (petiole). This leaf drop is caused by the feeding of maple petiole borers, Caulocampus acericaulis. Petiole borers are small insects called sawflies, which are non-stinging wasps. The sawfly is only about 1/6 of an inch long and emerges from the soil in the spring to mate and lay eggs near the base of the petiole of maple leaves.
Leaf drop is a frustrating problem because it's so hard to diagnose and correct ... and it may not even be a problem at all! Leaf drop is a normal condition of growth for many plants, whose lower leaves gradually die and fall off. Shock. This is the most common cause of leaf drop, but it can be the hardest to correct. In my experience, shock is most often caused by a sudden change in conditions.