May Flowers and Other Things

Tulip tree in flower

 

“ The first day of spring is one thing, and the first spring day is another. The difference between them is sometimes as great as a month.”

• Henry Van Dyke, Fisherman’s Luck

 

The first day of spring was in March and I feel like we have been gypped so far in 2019. The expected arrival of warm weather, or just sunny days for that matter, has not come upon us yet. The almost daily rains of April and May so make Seattle look dry by comparison. But enough griping about the weather. May is here and with it come the birds, flowers and butterflies that winter had kept at bay.

Eastern redbud trees flower in early May

Pinxter Azalea, Rhododendron periclymenoides, is a native rhododendron that has tubular pink and white fragrant flowers that appear just before the leaves expand. It is found in moist soils along stream or pond banks. Pinxters sometimes have a juicy, sweet “apple” gall formed by the fungus  Exobasidium vaccinaii.

Pinxter azalea flowers

Pinxter apple is really a gall

Native tulip trees, Liriodendron tulipifera,  bloom in May, and when they do, it is apparent how they received their common name. Yellow and orange flowers resemble tulips, standing upright among the flat-tipped leaves. This tree is sometimes called yellow poplar and is one of the largest trees in North America, sometimes reaching a height of over ninety feet.

Some native wildflowers are putting in their appearance now. One of my favorites is the diminutive gaywings or fringed polygala-Polygala paucifolia. Usually no taller than 6 inches, these plants may go unnoticed along woodland edges or peeking up out of needles lying under white pines in open woods. The magenta flowers have three petals, one of which is keeled and ends in a pink fringe.

Fringed polygala

Solomons’s seal is a native wildflower that is a good choice for use in woodland gardens. Its dangling white flowers along graceful, arching stems produce blue- black berries later in the fall. Hummingbirds will visit the fragrant, sweet smelling flowers. Geranium maculatum is another native wildflower that can be used in shade gardens.

Variegated Solomon’s seal

Swallowtail and other butterflies are seen regularly now that temperatures (rising at a glacial pace!) have warmed up and plants have leafed out. Painted ladies and red admirals have arrived from their southern wintering areas, and other butterflies should eclose from their chrysalises as the weather warms up. The gray hairstreak, one of the first hairstreaks besides the spring azure to make its appearance in May, should be out in warmer areas of Connecticut.

Gray hairstreak butterfly in May

Migrating birds have been a little slow to return, but thrushes, Orioles, tanagers and veerys arrived at their usual time when oaks are in flower. Warblers are pushing through on their way to their northern breeding grounds. Magnolia warblers arrive as crabapples are blooming and may linger around until it warms up. Listen for bird songs of warblers on Cornell’s allaboutbirds.org website, and then see if you can spot them with a pair of trusty binoculars.

Wilson’s warbler passing through on its journey north

Green tree frogs have been trilling during the day and turtles may be seen as they begin to look for mates and afterward for suitable nesting sites. Efts and salamanders may be seen on rainy days, or on sunny days following rains, and box turtles often are seen as they cross roads during or after rainy days. Things always perk up a little for me I see my first eft of the red-spotted newt out and about, usually in mid-May.

Eft form of the red-spotted newt

 

Of course, spring is not always a jolly time for gardeners. Lily leaf beetles, rose slug sawflies, asparagus beetles and gypsy moth caterpillars are here and carrying on with their plant damaging specialties. Check plants regularly to stop some of these pests in their tracks.

The harbinger of doom for true lilies and fritillarias- the lily leaf beetle

T

 

But it is May. And May is not, by nature, a limpid herald of doom, but rather a forerunner of the warm, sunny days to come. Cheer up, little buttercup! The best is yet to come.

Pamm Cooper

 

wild columbine and wild geraniums by a country roadside

 

Lily Leaf Beetles – UConn Looking for CT Volunteers to Assist with Biological Control Study

Just last week, as I peered into my tiger lily bed, a splash of red caught my eye. Even though I squashed every lily leaf beetle and larvae I found last year, some had apparently been missed and they overwintered to once more feast upon my lilies. The lily leaf beetle is native to Europe and is believed to have entered North America through plant shipments to Canada in the 1940’s. It was first confirmed in New England in 1999, when adult beetles were found in Boston. The bright red adults and rusty colored larvae have a voracious appetite for all kinds of true lilies – Asiatic, Trumpet, Tiger, Martagon, Oriental, Turk’s Cap, etc. as well as Fritillaria (Crown Imperials – although mine got a wilt and died back before the beetles came out) and our native Solomon seal (Polygonatum biflorum). Daylilies, which are not true lilies but instead in the Hemerocallis genus, are not affected. Occasionally lily leaf beetles are said to feed, but not reproduce, on hostas but this has not been a problem with the variegated ones in my gardens.

Red lily leaf beetles on tiger lilies, DMP

Adult, bright red lily leaf beetles overwinter in mulch and litter and emerge in the spring shortly after lilies begin to pop up and expand their foliage. The adults will feed on the leaves and flowers, mate and then females can lay more than 250 eggs on the undersides of lily leaves. The eggs will hatch in 8 days or so and then the larva will also start feeding on the leaves. To make matters worse, the larvae cover themselves with their own excrement. This is likely a defense mechanism to avoid being picked off as a menu item by birds and other predators. However, it makes squishing them unpleasant so while I will pick off beetles by hand, I admit that I use gloves for the larvae. If left to their own devices, the larvae will pupate, adults will emerge late summer and feed on any lilies left, drop to the ground to overwinter and come back to start this voracious cycle again next spring.

Lily Leaf Beetle, Donna Ellis, UConn

What’s a lily loving gardener to do??? Well, if you are a Connecticut resident join our control study!

Researchers at UConn are conducting a lily leaf beetle biological control project during the summer of 2015.  If you grow lilies in Connecticut, have a minimum of 12 plants in the lily family (Oriental lilies, Asiatic lilies, Turk’s Cap lilies, or Fritillaria) in your garden, and have lily leaf beetles feeding on them, we would like your help.  We will be introducing two species of beneficial parasitic wasps in June and would like to collect lily leaf beetle larvae from June through August. The parasitoid wasps attack lily leaf beetle larvae and over time these natural enemies will disperse from release sites and begin to spread through the state to reduce populations of lily leaf beetles.  The wasps were first introduced in Connecticut in 2012 and have also been released in Maine, Massachusetts, New Hampshire and Rhode Island, where they are establishing and starting to impact lily leaf beetle populations.  Please contact Gail Reynolds, Middlesex County Master Gardener Coordinator (gail.reynolds@uconn.edu; phone 860-345-5234) if you would like to participate in the research project.

Gail wants you to know that “the parasitoid wasps are very tiny, non-social, stingless wasps and that the wasps are not a panacea that will destroy the lily leaf beetles quickly. We encourage gardeners to tolerate the beetles and the (yucky) larvae so that we can collect and inspect them.  If they spray an insecticide or pick off the adults/larvae, then we can’t ascertain if the wasps are doing their thing.  We could potentially have had more parasitism occurring but we can’t confirm if the larvae are removed and killed without being examined.”

Lily Leaf Beetle Larva, Donna Ellis, UConn

Donna Ellis, UConn Senior Cooperative Extension Educator and Integrated Pest Management (IPM) Program Coordinator, who is coordinating this research project wants you to know that “The lily leaf beetle biological control project, funded in part by the U.S. Department of Agriculture, began in CT in 2012 with the release of two species of beneficial parasitoid wasps that will help reduce lily leaf beetle populations. The releases will continue this year, and Gail is looking for gardens throughout Connecticut. The releases have been made in all counties. To date, there has been one confirmed site where a parasitized lily leaf beetle larva was collected (New Haven County) in 2013. With additional numbers of beneficial wasps introduced each year in the state and the establishment of these biological control agents, we anticipate an increase in the number of parasitized lily leaf beetle larvae in the near future.”

LLB Parasitoid wasp release, created by Gail Reynolds, UConn

Gail will visit potential gardens to assess the lily, and lily leaf beetle populations, and she will release the parasitoid wasps, which are reared and shipped to CT from the University of Rhode Island (URI). Gail will also be doing most of the lily leaf beetle larval collections, to ship to URI where they will be examined to determine whether they are parasitized.  During the summer, Gail and Donna will receive training at URI so that we can examine the larvae at UConn.

Gail took the lead in creating a new fact sheet on lily leaf beetle biological control in Connecticut which can be found on the UConn IPM website: http://ipm.uconn.edu/documents/raw2/html/569.php?aid=569

Good gardening to you all!

Dawn

Dawn (with input this week from Donna Ellis and Gail Reynolds, UConn PSLA & Extension)

 

Who’s Eating my Plants this Time of Year?

There are a number of pests that are active this time of year, before the temperatures warm up a lot.  A few of these are slugs, spruce spider mites, and the lily leaf beetle.  I’ll say a little bit about each one of these, provide links to more information, and also put in some photos.  I have been seeing slugs on my Hosta.  I was out looking at them right after a rain and they were out during the day due to the extra moisture.  Slugs are usually nocturnal.  They become active as soon as the ground thaws in the spring.  There are a number of control measures for slugs including:  Reduce humidity in the garden by allowing space around the plants; trap slugs by placing a board on the ground supported by small stones overnight and drowning the slugs in soapy water; barriers around susceptible plants such as pine needles, crushed egg shells, diatomaceous earth, or copper wire (shocks them); or use beer traps, containers of beer sunken into the soil.  Non-alchoholic beer is effective.

 

Slug photo from www.noematic.org.

Unlike some of the other mites, the spruce spider mite is most active at cooler temperatures and does most of its damage in spring and fall.  Symptoms may be noticed some time after the damage has occurred.  Mite feeding results in a stippled spotting of the needles and gives them a bronze appearance.  Hosts include spruces, arborvitae, dawn redwood, Douglas-fir, hemlock, juniper, larch and pine.  Dwarf Alberta spruce is quite susceptible.  Check for spruce spider mites by tapping a few branches firmly over a piece of white paper or cardboard.  Mites will be about the size of a period in this text and will move slowly.  Natural enemies of spider mites often keep their numbers in check so chemical controls are recommended only if mites are numerous.  Horticultural oils or insecticidal soap are effective.  Predators of the spruce spider mite include lacewings, predatory mites (these move faster than the plant pests on paper), lady beetles and predaceous midges. 

Photos: Close-up of spider mite feeding symptoms on arborvitae (Penn State), Symptoms on dwarf Alberta spruce (Penn State) and an adult spruce spider mite (Univ. of  Maryland). 

The striking red lily leaf beetles are feeding now and will be laying their eggs from June into July.  Larvae will also feed on lily leaves during late July and early August.  They then drop to the ground, pupate, and emerge as bright red adults to feed until cold weather.  They overwinter as adults.  Adults can live for two years, so it is possible to see them from April through October.  The lily leaf beetle feeds and lays eggs on true lilies including Asiatic, Oriental, tiger and hybrid lilies but not daylilies.  Control of these beetles can be achieved using handpicking or insecticides labeled for this pest.  Read and follow all pesticide label instructions carefully.  This pest is a non-native insect thought to have arrived in the US on lily bulbs from Europe.

 

Adult lily leaf beetle (www.maine.gov) and larval stage (www.uoguelph.ca).

JA