Alonso Abugattus is the Naturalist at Long Branch Nature Center in Arlington County, Virginia. In 2010, he was asked to suggest the top 10 wildlife plants for various categories for home owners to use in the Chesapeake watershed by friends at Audubon at Home. Host plant (caterpillar food) information is according to Douglas Tallamy in the book Bringing Nature Home and this is important since some 96% of terrestrial birds feed on caterpillars (and sawflies) as major food sources when nesting. In fact, some birds we normally consider to feed on other sources (like hummingbirds and seed eaters) really need the insect protein to feed their young. No other insect group supplies as much of this valuable food source (as pointed out in Tallamy’s Bringing Nature Home), so when you plant these hosts, you’re also supporting birds and numerous other animals. For the next ten weeks, we will feature his suggested trees. We hope you will make comments and send us photos of your favorite wildlife trees.
Number 1. Oaks – No other group of trees that I’m aware of provides more wildlife value that the genus Quercus. Over 600 different insect species for example (mostly small wasps) use them exclusively for host plants, unable to survive on anything else. It also hosts more Lepidopteran species (543) than any other plant studied so far. Since caterpillars, along with sawflies, are the main component in the food of most terrestrial nesting bird species, these are incredibly important plants, without even considering the multitude of other creatures that also feed on them or their acorns, if not exclusively (over a 100 vertebrate species throughout the USA are known to eat acorns). Since the myriad of oak species have evolved to grow in most of the existing habitats and growing conditions, it comes down to finding the right plant (assuming you have the space for these trees).
A few to consider in our region:White Oak (Q. alba) – Some salt tolerance but can be affected by soil compaction. Chestnut Oak (Quercus prinus; syn. Quercus montana): Dry, terrace gravel Pin Oak (Quercus palustris) Shorter than many other oaks, tolerant of compaction, some salt and even flooding.