1997 Inspection Summary 



Siegfried Thewfie, Tom Durkis, and \on ]anis 



Cold injury led the list of problems plant growers 

 encountered early in the season Even pansies 

 can endure only so much cold weather, but with 

 bulging greenhouses and space at a premium, they 

 were often the first plants set outside As greenhouses 

 started opening up and growers were busy moving 

 stock outside, aphids appeared. The green peach aphid, 

 Myzus persicae, was the one most commonly encountered, 

 particularly in the southern part of the state. Necrotic 

 RING SPOT VIRUS, an ubiquitous problem on double im- 

 patiens seems to be getting worse each growing season. 

 Even some of the more conscientious growers were hit 

 hard by this disease. 



Before the season commenced, one nursery dealer 

 received a shipment of inkberry plants, Uex, that was 

 heavily infested with leafminers, Phytomyza sp The 

 plants were purchased from a Virginia broker, but actu- 

 ally originated from the Carolinas. Fortunately, the 

 dealer noticed that the leaves weren't quite normal and 

 had Division inspectors examine the plants. This in- 

 quisitive and observant plant dealer ultimately pre- 

 vented the distribution of the infested plants. 



Spider mite populations for nursery stock dealers were 

 high at some locations. Overcrowding, buying infested 

 stock, lack of inspection, and dry temperatures contrib- 

 uted to a healthy spider mite population. Tropical house 

 plants seemed to be the most common host. Annuals 

 such as marigolds, salvia, zinnia, dahlia, helianthus, and 

 ipomoea were frequently infested, along with many herbs 

 and perennials. Hollyhock, lilies, roses, scabiosa, and 

 salvia all were listed as having heavy mite populations 



Inspectors once again found thrips to be the number 

 one greenhouse pest. Greenhouse thrips, Heliotkrips sp., 

 commonly infested houseplants like nephthytis and 

 dieffenbachia while western flower thrips, Frankliniella 

 ocddenlalis, had a number of favorite hosts. Annuals such 

 as scaevola, brachycome, impatiens, ageratum, snapdragon, 

 gazania, marigold, portulaca, verbena, and cleome were all 

 good indicator plants. Some perennial plants are also 

 attacked but, when placed outside, their thrips popula- 

 tions are not as prolific in an uncontrolled environment 

 and succumb to predators like the minute pirate bug. 



The LILY LEAF BEETLE, Lilwcens UlU, was found in New 

 Hampshire for the first time in 1997. Reports of lily 

 damage by this pest in IVlassachusetts and Rhode Is- 

 land have been mentioned since 1992. It wasn't until 

 early June of 1997 that a couple of adult beetles along 

 with some eggs were collected on lily plants growing in 

 Raymond, New Hampshire, with additional adults col- 

 lected in Stratham during early August The bright scar- 



let beetles are very noticeable, feeding on a wide vari- 

 ety of lily hosts but only find Lilium sp and Fritillaha sp 

 suitable for egg deposition. Researchers in Rhode Is- 

 land are working on various beneficial insects and some 

 are already showing encouraging prospects that may 

 help to control this pest 



Asian long-horned beetles (ALHB), Anaplophora 

 glabripenis, affecting Brooklyn, New York neighborhoods 

 occupied many newspaper headlines Because of all the 

 notoriety these beetles received, our office was inun- 

 dated with calls and insect specimens sent in for iden- 

 tification. The beetles are considered to be extremely 

 destructive to hardwoods and look similar to our com- 

 mon white-spotted long-horned beetle. Fortunately, to 

 date, no ALHB have been found in New Hampshire. 



Elongate hemlock scale (Fiorinia scale), Fiorinia 

 externa, was found on B&B hemlock nursery stock This 

 is the first reported collection of this insect pest in 

 New Hampshire. An attempt to determine the state that 

 the trees originated from proved unsuccessful. However 

 the New Hampshire broker who distributed the trees 

 assisted in helping to locate, recover, and destroy all 

 known infested stock Hemlock trees surrounding the 

 contaminated nurseries were examined and found free 

 from any scale and all of the areas will be scouted 

 again this coming year. 



White pine decline, a condition that Maine patholo- 

 gists think might be brought about by tree stress result- 

 ing from the 1995 drought, was especially noticeable in 

 towns throughout Carroll county and in many central 

 and southern IVlaine counties as well. Browning foliage, 

 flagging tips and branch mortality, and, occasionally, 

 tree mortality were all symptoms. The fungus 

 Caliciopsis pinea was found causing cankers on white 

 pine. Infected trees exhibited excessive pitch flow on 

 tree boles, characteristically 20-30 feet above the 

 ground. There are differences of opinion as to just what 

 is causing the problem, but everyone is in agreement 

 that numerous white pine trees are suffering from either 

 physiological, insect, disease, or unknown causal agents 

 or a combination of all of the above. Damage was most 

 severe on poor growing sites and, with the lack of rain 

 this season, trees may see further evidence of this 

 malady in 1998. 



A full report can be obtained by contacting the Division of 

 Plant Industry, State Lab Building, Lab D, 6 h\azen Dr., 

 Concord. NH 03301; phone number (603) 271-2561 or 

 email insecla@compuserve.com. 



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THE PLANTSMAN 



