BIOLOGY, ECOLOGY, AND MANAGEMENT OF LINDEN BORER, A SERIOUS INSECT PEST OF SHADE TREES IN NURSERIES AND URBAN LANDSCAPES IN WISCONSIN

• Sponsoring Institution: National Institute of Food and Agriculture
• Project Status: TERMINATED
• Funding Source: HATCH
• Reporting Frequency: Annual
• Accession No.: 0193659
• Project No.: WIS04689
• Project Start Date: Oct 1, 2002
• Project End Date: Sep 30, 2004

Project Director
Williamson, R. C.

Recipient Organization
UNIV OF WISCONSIN
21 N PARK ST STE 6401
MADISON,WI 53715-1218

Performing Department
ENTOMOLOGY

Non Technical Summary
Linden borer larvae are reported to feed and/or mine under the bark of several linden tree species, including basswood. Subsequent larval feeding typically results in the decay of damaged feeding cavities or chambers, ultimately causing tree death. The goal of this research is to gather valuable information on the biology, ecology and management of linden borer. Such information will enable appropriate management recommendations to be derrived and implemented. Addiionally, valuable biological information on linden borer will be generated.

Animal Health Component

(N/A)

Research Effort Categories

Basic

30%

Applied

70%

Developmental

(N/A)

Classification

Knowledge Area (KA)	Subject of Investigation (SOI)	Field of Science (FOS)	Percent
211	2110	1130	50%
216	2110	1130	50%

Knowledge Area
211 - Insects, Mites, and Other Arthropods Affecting Plants; 216 - Integrated Pest Management Systems;

Subject Of Investigation
2110 - Ornamental trees and shrubs;

Field Of Science
1130 - Entomology and acarology;

Keywords

plant insect resistance

chemical control (insects)

pest management

cerambycidae

integrated pest management

tilia

woody ornamentals

insect larvae

insect behavior

shade trees

insect biology

insect ecology

insect management

nurseries

urban areas

landscapes

life history

oviposition

pupation

plant insect relations

insect surveys

injections

application methods

pesticide application

adults

emergence

Goals / Objectives
OBJECTIVE 1: To determine the life history of the linden borer, adult oviposition (location and number of eggs laid), larval behavior, and pupation site of linden borer within Wisconsin. OBJECTIVE 2: To evaluate the effectiveness of plant resistance (i.e., cultivar resistance) and insecticide treatments as effective management tactics for control of linden borer in Wisconsin.

Project Methods
A biological survey will be conducted at respective insect museums in the Great Lakes Region. Data will provide a regional perspective on adult activity, thus contributing to the determination of linden borer life history. Field studies will be conducted at a nursery with a confirmed history of linden borer activity. Infested Tilia cordata cv 'Greenspire' trees will be identified, thereafter insect rearing cages will be placed over eight infested linden trees, completely enclosing selected trees with a screened mesh cover that permits over 95% light. Caged, infested linden trees will be monitored weekly beginning in late-April and continuing through early-October. Additional T. cordata cv. 'Greenspire' trees infested with the linden borer will be examined for 1) oviposition location on and within the plant, 2) larval location, and 3) pupal location. Respective trees will be destructively sampled by dissecting each tree systematically into lateral cross-sections to determine the precise location of each of the aforementioned data. These data should provide an accurate life history and biological perspective of S. vestita in Wisconsin. Management tactic (1) Five Tilia cordata cultivars, 'Chancellor,' 'Corinthian', 'Greenspire,' 'Glenleven' and 'Redmond,' will be established at each study site as described above. Treatments (i.e., cultivars) will be arranged in a randomized complete block design with eight replications per treatment. Each tree will be examined monthly for oviposition events and sites as well as insect frass from late-April through early-October. This objective will be conducted over the duration of this proposed project. Data will provide insight as to susceptible Tilia cultivar(s) of the linden borer. Management tactic (2) Twenty-four previously established Tilia cordata, cv. Greenspire trees with have evidence of linden borer larvae will be randomly selected at the previously described nursery. Eight randomly selected trees will receive a soil drench application of a systemic insecticide, thiamethoxam, eight will receive a soil drench of imidacloprid, and eight trees will remain untreated. Each treatment will be applied at respective labeled rates (1.0 g and 1.42 g active ingredient per 2.54 cm diameter at breast height (DBH), thiamethoxam and imidacloprid, respectively. Insecticide, soil drench, applications will be applied to each respective tree using a 30 gallon spray tank equipped with spray applicator hand-gun. Soil drench applications of respective insecticide treatments will be made roughly one meter from the tree trunk of the tree. An application volume of 7.5 liters per 2.54 cm DBH will be used for the drench application. Treatments will be applied in year one of this project. All the trees in this experiment will be harvested, dissected (as described in objective one), and examined in year two to determine the absence or presence. These data will provide information as to the effectiveness the systemic insecticide treatments for control of the linden borer when applied as a soil drench.

Progress 10/01/02 to 09/30/04

Outputs
This project terminated September 30, 2004; subsequently, one peer-reviewed manuscript has been submitted for review (Johnson and Williamson) and two additional manuscripts are in preparation. The objectives of this research were to better understand the biology, ecology, and management of the linden borer, an imporant insect pest of city, urban, and nursery trees in Wisconsin. The results of our research suggest that the linden borer has between five to six instars. We also discovered that curative (i.e., corrective) insecticide treatments are not effective in controlling the linden borer infested trees greater than 38 cm (15 inches)Diameter at Breast Height (DBH). It was determined that linden borer adults are active between June and early-September in Wisconsin. This information is highly valuable in developing pest management strategies; it is plausible that bark spray applications can be made prior to adult emergence to prevent larval infestations and damage. This research suggests that various cultivars of Tilia cordata and Tilia americana were equally suceptible to linden borer. Lastly, a chipping management study revealed that chipping Tilia infested trees to a 5.1 square centimeter (0.8 square inches) or smaller chip size effectively destroyed linden borer larvae and pupae. The information gained from this study will provide valuable information to pest managers that will aid them in developing appropriate management strategies for this important pest.

Impacts
The goal of this research is to gain a better understanding of the biology of the linden borer; subsequently such information may provide valuable insight toward developing respective management strategies of this important woody ornamental insect pest.

Publications

• Johnson, T.A. and R.C. Williamson. 2004. Multiple morphological measurements as an indicator for the larvae of the linden borer, Saperda vestita Say (Coleoptera: Cerambycidae). (submitted 12/04)
• Johnson, T.A. and R.C. Williamson. 2005. Potential management strategies of the linden borer, Saperda vestita Say, (Coleoptera: Cerambycidae) in urban landscapes and nurseries. (in preparation)
• Johnson, T.A. and R.C. Williamson. 2005. Cultivar preference of the linden borer, Saperda vestita Say, (Coleoptera: Cerambycidae, in Tilia spp. (in preparation)

Progress 01/01/03 to 12/31/03

Outputs
Since beginning this project numerous investigations have been conducted, including: 1) establishment of two species and several cultivars of Tilia cordata and T. americana for the purpose of determining host preference; 2) Application of systemic insecticide treatments for possible control of linden borer larvae in infested urban street trees; 3) Evaluation of the effects of two commercial wood chipping devices for determining the likelihood of larval survival when subjected to such treatments; 4) Determination of larval instar distribution of linden borer larvae; and 5) Determination of seasonal biology (i.e., life cycle) of linden borer in Wisconsin urban landscapes.

Impacts
The goal of this research is to gain a better understanding of the biology of the linden borer; subsequently such information may provide valuable insight toward developing respective management strategies of this important woody ornamental insect pest.

Publications

• No publications reported this period

Progress 01/01/02 to 12/31/02

Outputs
This project was recently initiated in October 2002, subsequently only a small portion of this study has been conducted. To date, respective soil injection insecticide treatments have been applied to infested linden trees in the city of Milwaukee. Additional linden trees will be injected in April 2003 with another insecticide treatment. Also, in the spring of 2003, field cages will be put in place to monitor adult emergence from the respective linden trees.

Impacts
Because the linden borer is an important insect pest that causes serious damage to nursery, urban street, and landscape trees, and the biology is poorly understood, information generated from this study will enable appropriate management recommendations to be derived, communicated, and implemented.

Publications

• No publications reported this period