General Conditions: Over the past two weeks, sunny weather with high temperatures mostly in the 80s and some 90s continued to be the norm. Hanson received 0.90 inches of rain, having received 0.65 inches of rain today, Aug. 10th, which dampened the soil slightly. Before the rain today, unirrigated soils were dry and dust-like to a depth beyond 12 inches. This brief rain will take a bit of the stress off plants, but more rain is drastically needed. The following plants are in full bloom: Clerodendron trichotomum, Albizia julibrissin, Campsis radicans, Aesculus parviflora, Clethra alnifolia, Hydrangea paniculata, Hydrangea macrophylla, Hydrangea quercifolia (Oakleaf Hydrangea), Hydrangea arborescens (Smooth Hydrangea), roses, Rose-of-Sharon, Echinops ritro (Globe Thistle), Rubus odoratus, Lobeliasiphilitica, Phlox paniculata (Garden Phlox), Echinacea sp., perennial Hibiscus, Hosta plantaginea and other late blooming hosta, Persicaria polymorpha, Lythrum salicaria, Liatris spicata, Lysimachia clethroides, Perovskia atriplicifolia, daylilies, Shasta daisy, Nepeta sp., Joe-pye-weed, Heliopsis ‘Summer Sun’, Helianthus sp., Hollyhocks, Monarda didyma (Beebalm), Silphium sp., Actaea racemosa, Veronicastrum virginicum, Rudbeckia triloba, Rudbeckia fulgida, Rudbeckia ‘Herbstonne’, Coreopsis sp., Astrantia major and Campanula sp. Unfortunately, the heat and drought have pushed many plants to reduce or end bloom early.
Pests/Problems: The biggest landscape problem right now is probably the drought. Most areas in MA are in a severe to moderate drought watch. In unirrigated landscapes, lawns are brown; some trees are dropping leaves or displaying “premature fall color”, marginal foliar browning is occurring on many plants, etc. When daylilies and hosta start to wilt, collapse and turn brown, then we know it is really dry. When plants reach their permanent wilting point, they sometimes will not recover. The constant reminder this season continues to be: urge clients to water drought-stressed plants, especially those of high value and those defoliated by gypsy moth caterpillars this season. Unfortunately, many towns are on partial or total water bans. Many of the oak trees defoliated by the caterpillars have yet to put out that second flush of significant foliage. It is a challenging season for growing and maintaining plants. .
The drought has, so far, reduced the mosquito population. This could change if we get rain. Although the mosquito numbers are down, do not let down your guard down and still continue to use repellents like DEET. As mentioned in the last message, a mosquito tested positive for EEE (Eastern Equine Encephalitis) in Middleborough, MA and according to reports, West Nile Virus (WNV) can flourish in dry conditions. Supposedly, as natural water supplies dry up, some species of mosquitoes that carry WNV, find breeding sites in other areas of standing water: bird baths, pools, plant saucers, etc. The take home message is to have clients empty and change containers of water frequently or use Bacillus thuringiensis israelensis.
As many people know, there are many tick borne diseases (http://www.cdc.gov/ticks/diseases/index.html), and deer ticks are vectors for several of those diseases, including Lyme disease. For everyone working in or enjoying the outdoors, it is important to be able to recognize the symptoms of Lyme disease. Here is a link from the Center for Disease Control (CDC):
http://www.cdc.gov/lyme/signs_symptoms/. Recently, a friend who works outdoors reported that she had Babesiosis (http://www.cdc.gov/parasites/babesiosis/,
Japanese beetles remain active but appear to be few in number. Asiatic Garden beetles and Oriental beetles also appear few in number. Peak emergence of Asian Longhorned Beetle (ALB) is usually in August and this insect attacks healthy trees. Monitor susceptible trees like maples, horsechestnut, elm, poplar, willow, etc. (For more information, see Tawny Simisky’s Insect section of the Landscape Message.)
Continue to monitor for the following insects and manage if needed: viburnum leaf beetle; spider mites; redheaded pine sawfly; introduced pine sawfly; Andromeda, rhododendron and azalea lacebugs; aphids; snail; slugs and leafhoppers. Remember to be cautious when applying pesticides in hot weather and always read the label.
Damage to flowers of Echinacea, Rudbeckia, marigolds, Helianthus, Bidens, Heliopsis, and other plants in the composite (Asteraceae) family, from the sunflower moth caterpillar is really beginning to show up, with the center cone of the flowers turning a black-brown and looking messy from all the frass.
Monitor dogwoods for dogwood sawfly.
Rabbits, deer and chipmunks continue to browse.