Bill Dunson 10/5/16 Bill Dunson 10/5/16

Signs of Fall Abound

Our weather is showing some cool night time temperatures, but frost is still 2-3 weeks away and there is lots of insect activity and still some late bird migration underway. Fall fruits are much in evidence, offering immediate snacks and some long term food supply. One of my favorites is the blue fruit of arrow wood viburnum. They are small enough for many species to eat and we have so many plants that they last into the fall. In contract, the winterberry hollies in our marshes are very bright red and seem to be a fruit that is not eaten so early as the viburnums. Isn't it interesting that such different colors are both so attractive to birds?

Caterpillars are still present in large numbers, many preparing to overwinter as pupae. This rarely seen marsh dagger moth caterpillar was especially interesting since they were present in very large numbers in the open, eating cattails, and their color is quite bright. This would normally indicate that the caterpillars were toxic but I could find no information on this topic. In distinct contrast the caterpillars of snowberry clearwing sphinx moths or hornworms are extremely well camouflaged. They can damage our coral honeysuckles severely, so I move many of them to the exotic Japanese honeysuckles where they do no harm. A few caterpillars fall prey to the very painful assassin or wheel bug which is shown here eating an army worm. You must be careful not to pick up this bug or it may inject you with a painful bite.

Monarchs are still passing through our area and here a beautiful female is finding some nectar on an aster, characteristic of the fall season. The meadowhawk or yellow legged dragonfly is the last dragonfly to emerge in the north, a beautiful "fall color" and a true indicator of the fall season.

Bird migration is quickly passing although we are still enjoying some warblers. This Cape May male was spotted feeding on wild grapes near the Blueridge Music Center. During spring migration the same species is very fond of the flowers of sea grapes in our Florida yard. Nearby we spotted a flock of seven wild turkeys which all appeared to be young males or jakes, since their beards were of intermediate length. Some hawks are migrating through and others will remain during the winter. An immature red-tailed hawk was engaging in some amusing aerial dogfights with three ravens; it is here shown upside down as it buzzes one raven below.

So fall with all of its beauties is here with a vengeance- there is no stopping the seasons and we would not want to. Enjoy the changing parade of nature and savor each moment.

Bill Dunson
Galax, VA and Englewood, FL

Bill Dunson 8/8/10 Bill Dunson 8/8/10

Marvelous milkweeds

I am a huge fan of milkweeds due to their special attraction not only to monarch butterflies but also to a considerable list of other insects that are milkweed specialists, and some generalists who use milkweeds as a community to forage in. But the problem is that those of us that own hay fields will cut the grass including the milkweeds once or usually more per year, slaughtering the marvelous milkweeds. However I have come up with a compromise that I think both feeds the cows, and preserves the milkweed community. See what you think of my solution.

My plan is to cut the grasslands only once per year and that is in mid to late June in our location here in the SW Virginia mountains. This serves not only to harvest the grass for use in fodder but removes woody vegetation that invades the grasslands, and removes a layer of cold-season grasses (such as fescue) that are primarily exotic to this area. This releases the warm-season grasses and allows them to grow and produce a crop of seeds by Fall for use by native birds. But you may ask what about the milkweeds and their fate? It appears to me that this regime may actually be beneficial to the milkweed community in the following way. I retain a certain number of fields that are not cut except very occasionally (they are burned every three years in late Winter) and which have natural populations of milkweeds (in this case mainly the common milkweed, Asclepias syriaca). The fields that were cut this year on June 17 began about seven weeks later in early August to produce a wonderful crop of milkweed flowers, while the uncut milkweeds are setting seed and are no longer blooming. The leaves of the uncut milkweeds are old and tough whereas the cut and regrown milkweeds have young tender leaves. Thus my single-cut method of harvesting hay fields stretches out the milkweed season but does not obliterate it, as would happen if the fields were to be harvested a second time, a common practice among farmers to maximize hay production. Also I have noticed that the monarchs often do not arrive in this area in time to fully utilize the naturally cycling milkweeds, and indeed seem to use the "second crop" milkweeds extensively.

Some illustrations of the re-grown milkweeds are shown in photos of an adult monarch gathering nectar from a "second crop" flower, of a female yellow morph tiger swallowtail also nectaring on a re-grown plant, and a monarch caterpillar feeding on a re-grown leaf. Surely there is much yet to learn about the characteristics of milkweeds that are cut and then sprout again- do they provide proper food at tolerable levels of toxins, and in a timetable that is appropriate? Certainly it appears from my observations that this is a win-win situation that can preserve the habitat of many species that depend on milkweeds while also providing some income for the farmer. Of course subsequent hay cuttings must be sacrificed for the pleasure of observing and fostering the milkweed animal community, and providing enhanced food and cover for birds in Fall and Winter.

One of the other lesser known insects that I encounter among our milkweeds is a bit sinister- the famous assassin or wheel bug (see photo)! It is a predator with a wicked beak, a poisonous bite and a reputation for delivering a painful zap with its tubular mouth. It eats insects that come to the milkweeds and it would be interesting to observe whether it is capable of devouring those that are protected by the milkweed toxins, in contrast to others such as tiger swallowtails that are not.

So many puzzles and so little time! So get out there and check out the milkweeds and their fascinating inhabitants.

Bill Dunson

Galax, VA

Englewood, FL