For those of you headed into the field this weekend, these notes may be of interest in locating species of interest:
July marks the transition from summer nectar sources to the early fall bloomers. Already some of the early species of goldenrod are beginning to flower, and blossom heads are expanding on ironweed and Joe-pye weed, as well as on the many other boneset species. In the garden, mints and mint relatives like oregano and thyme are powerfully attractive to hairstreaks and sulphurs. Late summer butterfly magnets like butterfly bush, sedum, lantana and zinnias will soon be visited by clouds of grass skippers – but not just yet.
Milkweed and dogbane are fading on the Eastern Shore and Piedmont; butterfly weed also fading west of the mountains. Where early mowing cut down the initial growth there may be a good bloom still (or even a second bloom). In the mountains, there is still good milkweed, and spotted knapweed and other late summer roadside flowers are hitting their stride. Knapweed in particular is a magnet for Northern Metalmark along Allegany Co. back roads.
Pickerel weed is at peak along the margins of many local ponds and lakes, and attracts numbers of skippers, especially Broad-winged. In coastal locations, check pickerel weed also for less-common skippers like Salt Marsh, Rare, Delaware, and Dion.
The summer bloom of buttonbush is finished at Eastern Neck NWR (where liatris is coming on and pulling in skippers, and Joe-pye and ironweed should begin blooming this weekend or next – there’s plenty of nectar there). July 4 butterflies in the garden at Eastern Neck included American Snout, many Black Swallowtails, Viceroy, Coral and Gray Hairstreaks, and a few freshly emerged Red Admirals (also scarce earlier in the summer).
Look for Giant Swallowtail along the Potomac, where it uses the larval host Ptelea trifoliata (wafer ash or common hop-tree), which is also in the Rutaceae along with the swallowtail’s usual hosts of citrus and common prickly-ash.
Check out flowers under and around Eastern Red-cedar for Olive (Juniper) Hairstreak, fresh into its second brood and reported from southeastern PA this week. Banded Hairstreak may be experiencing an extended emergence, with photos of a very fresh specimen coming in this week from central MD. Older specimens were about at Ft. Indiantown Gap PA last weekend. Devil’s walking stick (Aralia spinosa) is coming into bloom, and should be checked wherever it occurs for hairstreaks.
Roadside partridge pea and other senna-type plants could host ovipositing Cloudless Sulphurs (which are now beginning to show up in numbers as far north as Massachusetts) and Little Yellow (which has unaccountably not yet been reported in the region this year). Sleepy Orange was regularly seen in its first brood earlier in the year and should be emerging now in a second flight using the same hosts.
Wild Indigo Duskywings are in flight now, especially near patches of Pennsylvania crown vetch, which it has adopted as a larval host in addition to its Baptisia namesake. Horace’s Duskywing is also out , so be sure to check for the cell-end white spot on the DFW. Cloudywings (Northern and Southern can be expected almost anywhere, much more rarely Confused) are flying now too and may be mistaken for duskywings; both are quite fond of red clover. You might confuse the newly emerged second brood of Common Sootywing for a duskywing or cloudywing at first glance; they’re having a good second flight. Sachem is back in a new brood and should be commonplace within the next week, then faded into masquerading for less-common skippers by month’s end.
Weather permitting, Tom and I will be in Garrett Co. this weekend looking for Aphrodite and Atlantis Fritillary and Bog Copper at Cranesville Swamp and environs. Means forgoing, for the moment anyway, another trip down to Wicomico Co. where it is reported that King’s Hairstreak has finally made its appearance this week.
The Regal Fritillary show at the annual open house/tour at Ft. Indiantown Gap PA was amazing on July 5; Beth and I went up for it and ran into a number of folks from both washbutterflies and PALepsOdes. Conservatively, we saw hundreds of Regals, mostly males as the females were just emerging. Common milkweed was waning on the National Guard training grounds but dogbane and butterfly weed was in full bloom and expected to continue this weekend for the final 2013 tours Thursday July 11 and Friday July 12. Aphrodite Fritillary, Meadow Fritillary, Variegated Fritillary, and Great Spangled Fritillary were also flying with the Regals, sometimes all five together on the same plant, and most milkweed clumps also sported a Coral Hairstreak or two. American Ladies were common, ovipositing on pussytoes along the first part of the walking tour route; American Coppers were also out in numbers. Clouded and Orange Sulphurs were flying together on the reservation. We also observed about a dozen Baltimore Checkerspots in other wet meadows around Ft. Indiantown Gap. If you’ve never doing the FIG fritillary and grassland tour, go this week or watch for the 2014 dates (usually two weekends around July 4).
Please let me know what you find this weekend so I can share it with others, and I hope to run into you in the field!
Follow mid-Atlantic butterfly sightings at https://leplog.wordpress.com and on Google Groups at MDLepsOdes.