Ashfalls also affect insect populations, which are severely limited by ashfalls greater than 25 mm (1 in). This may have a beneficial effect if pastoral and crop-pest populations are reduced due to the ash. Highly mobile insects, many of which have a dense covering of body hairs which can trap the tiny ash particles, such as honey and pollination bees, are more susceptible to ash than smooth-bodied insects such as beetles.
Fine ash can also serve as effective mulch, improving water retention of soil.