General Conditions: This 2017 spring continues to be one of the most colorful springs in near and distant memory. Cooler temperatures and sufficient rain continue to hold bloom this past week. Daytime temperatures started out on May 4th and 5th in the low 60’s, but the fell to the 40’s-50’s, with 37 degrees noted on the early morning of May 9th. Hanson received 1.1 inches of rain this past week and soils remain moist. The following plants are, or remain, in full bloom:
Cercis canadensis (Eastern Redbud), late blooming magnolias like Magnolia ‘Elizabeth’, Kwanzan cherry, Malus sp. (apples, crabapples), Cornus florida (Flowering dogwood), Daphne x burkwoodii 'Carol Mackie', Daphne tangutica, Chaenomeles speciosa (Common Floweringquince), Viburnum ‘Eskimo’ and other viburnums, Syringa vulgaris (Common Lilac), Halesia sp., Pieris floribunda (Mountain Pieris), Spiraea prunifolia f. simplicifolia (Bridalwreath Spirea), Fothergilla major (large Fothergilla), Fothergilla gardenii (dwarf Fothergilla), Flowering Almond, Kerria, Vaccinium corymbosum (highbush blueberry), Rhododendron ‘Olga Mezitt’, Lonicera tatarica (invasive), Exochorda racemosa, Cytisus scoparius (Scotch broom) and Ilex x meserveae. Epimedium sp., Trillium sp., Galium odoratum (Sweet Woodruff), Brunnera macrophylla, Asarum canadense, Polygonatum sp. (Solomon's Seal), Stylophorum diphyllum (Wood Poppy), Phlox subulata, Aurinia saxatilis (Basket of Gold), Phlox divaricata, Arisaema sp.(Jack-in-the-pulpit), Primula sp., Pulmonaria sp., Ajuga, dwarf bearded Iris, Saruma henryi, Lamiastrum galeobdolon, Lamium sp., Dicentra spectabilis, Lunaria annua (honesty or money plant), Mertensia virginica (Virginia bluebells), Glaucidium palmatum, Helleborus foetidus, Violets and Vinca minor . The following plants are beginning bloom: Magnolia fraseri, Rutgers hybrid dogwoods (Stellar series), Weigela florida ‘Versicolor’, Wisteria floribunda (Japanese Wisteria), Calycanthus floridus (Common Sweetshrub), Geranium sp., Camassia sp., Persicaria bistorta ‘Superbum’, Corydalis lutea, Tiarella cordifolia (Foam Flower) and Convallaria majalis (Lily-of-the-valley).
The following plants are ending bloom: Viburnum carlesii (Mayflower Viburnum), Viburnum x burkwoodii ‘Mohawk’, Rhododendron ‘PJM’, Rhododendron schlippenbachii (Royal Azalea), Spiraea thunbergii ‘Ogon’, Azalea ‘April Snow’, Helleborus x hybridus, daffodils and tulips.
The wet weather has delayed mowing and landscape operations. Once again, if using a preventative grub management product that contains Chlorantraniliprole (AceleprynTM, GrubExTM), it is best applied before the end of May; follow the directions on the label before applying.
Pests/Problems: In the Hanson, MA area, winter moth caterpillars are actively feeding, often found at the leaf tips between webbed leaves and most winter moth caterpillars are at 3rd instar, although a few 2nd instars were observed. (540 growing degree days (GDD) at Base 40). Many maples have leafed out and damage by winter moth is dramatically reduced from previous years, HOWEVER, gypsy moth caterpillars in high numbers were present on Norway, Japanese, sugar and red maples, feeding alongside the winter moth caterpillars. Both caterpillars were also found feeding on: oak, rose, crabapple, apple, blueberry, beech, etc., so even though winter moth caterpillar numbers are down, gypsy moth caterpillar numbers are high and damage is beginning to show. Continue to monitor host plants and manage these caterpillars when they are small. (See Tawny Simisky’s Insect Section of the Landscape Message).
Gypsy moth hatch was completed and the small (about the size of a thick eyelash), black caterpillars have been ballooning and landing everywhere. Three people in Hanson reported and displayed skin rashes on necks and arms from gypsy moth caterpillars landing on them while they were outside gardening. The recent and continued rain and drizzle, hopefully will contribute to activating the Entomophaga maimaiga fungus which could help reduce the gypsy moth caterpillar population.
Deer tick nymphs usually become active in May and are active for several months; so be on the lookout! Deer tick nymphs are very tiny and it is this stage that is usually most responsible for the transmission of Lyme disease. Recent news has also highlighted the other diseases that may be carried and transmitted by deer ticks. Be vigilant, conduct tick checks frequently and take precautions like using repellents when working outdoors.
Lily leaf beetle adults remain active on true lilies and egg-laying has begun. Hand-pick and destroy the adults when possible, or manage with a labeled insecticide. Check beneath the foliage for the tan-red-dark-colored eggs and prune out and destroy. Monitor the undersides of azaleas for azalea whitefly, and manage if found. Eastern tent caterpillar remains active and webs are noticeable, mostly on wild cherry; although numbers, as in past years, appear to be down in many areas of Plymouth County. Snowball Aphid remains active and aesthetic damage is apparent as curled foliage. The White-spotted Pine Sawyer (native insect) may soon, if not already be active. This large insect is often mistaken for the Asian longhorned beetle, which emerges later in the season.
Continue to monitor for European pine sawfly; boxwood psyllid; hemlock woolly adelgid, spruce spider mite and Elongate hemlock scale. The following insects are also active: black flies, carpenter bees, ants, wasps, slugs and dog ticks. Beneficial insects like, the beautiful, bright green, six-spotted tiger beetle (Cicindela sexguttata) are active.
With the recent rain, the bright, orange, jelly-like galls of cedar-apple rust (Gymnosporangium) continue to be seen on Eastern red cedar and other junipers.
Dogwood anthracnose disease, (often characterized by lower branch dieback) is a fungal disease of flowering dogwoods and Pacific dogwoods which are susceptible to infection during wet springs, as new leaves and shoots are emerging. Consider managing high value trees and protect new growth with a labeled fungicide, according to label directions.
Dandelion remains in flower although a few plants have started to set seed. Veronica, garlic mustard, ground ivy, violet, and chickweed remain in bloom. The Massachusetts invasive plants Euonymus alatus (burning bush) and barberry are also in bloom. To prevent seed formation and subsequent future dispersal of these invasive plants, prune or sheer back now to remove the flowers.
Immediately after bloom is a good time to prune, or renovate, spring-flowering trees and shrubs, like Spirea, lilac, Forsythia, azaleas and rhododendrons before flower buds are set for next year.