Pine Shoot Beetle

The pine shoot beetle (Tomicus piniperda L.), a serious foreign pest of pines, was discovered at a

Christmas tree farm near Cleveland, OH, in July

1992. A native of Europe, the beetle attacks new

shoots of pine trees, stunting the growth of the trees.

The pine shoot beetle may also attack stressed

pine trees by breeding under the bark at the base of

the trees. The beetles can cause severe decline in

the health of the trees, and in some cases, kill the

trees when high populations exist.

The U.S. Department of Agriculture’s (USDA)

Animal and Plant Health Inspection Service (APHIS)

has taken steps to prevent this insect from moving to

major pine tree-production areas. To date, APHIS, in

cooperation with State officials, has quarantined

counties in Illinois, Indiana, Maryland, Michigan, New

Hampshire, New York, Ohio, Pennsylvania, Vermont,

West Virginia, and Wisconsin. Surveys are 

completed each year to monitor the natural spread

and artificial movement of the pine shoot beetle.

Through detection surveys, the beetle has been

found in pine tree-production areas including

Christmas tree farms and nurseries. Pine shoot 

beetle has also been detected in mature pine stands

and areas surrounding mill yards that process pine

logs. The beetle prefers Scotch pine, but it will feed

and reproduce on most, if not all, species of pine.

Natural dispersal of the pine shoot beetle can

occur when the beetles emerge from their overwintering sites. Studies show beetles are capable of dispersing 2 km in the wind.

Artificial dispersal to uninfested areas can occur

through the movement of infested pine Christmas

trees, pine nursery stock, bark mulch, and pine logs.

Appearance and Life Stages

Adult pine shoot beetles are 3 to 5 mm long, or

about the size of a match head. They are brown or

black and cylindrical. The legless larvae are about 5

mm long with a white body and brown head.

Pine shoot beetles complete only one life cycle

per year. They spend the winter months inside the

thick bark at the base of living pine trees.

The beetles become active and leave their overwintering sites in March and April (when temperatures reach 54 °F) to mate and lay eggs in dying or

stressed pine trees, pine trees and stumps which

have been recently cut, logs, and bark mulch. Adults

have been shown to fly several kilometers during this

period in search of a suitable host. To create a place

to lay their eggs, females bore gallery systems

between the inner bark and outer sapwood of the

host. Egg galleries are 10 to 25 cm long.

From April to June, larvae feed and mature under

the pine bark in separate feeding galleries that are 4

to 9 cm long. When mature, the larvae stop feeding,

pupate, and then emerge as adults. From July

through October, adults tunnel out through the bark

and fly to new or 1-year-old pine shoots to begin maturation feeding. The beetles enter the shoot 15 cm

or less from the shoot tip, and move upwards by hollowing out the center of the shoot for a distance of

2.5 to 10 cm. Affected shoots droop, turn yellow, and

eventually fall off during the summer and fall.

Feeding adults attack shoots of living pine trees of all

sizes, mainly in the upper third of the tree. This is the

most destructive stage of the life cycle. When shoot

feeding is severe, tree height and diameter growth

are reduced. The tree can be weakened to the point

where the beetles can attack the trunk of the tree and

use it for egg laying.

History

The pine shoot beetle is reported to be the second most destructive shoot-feeding species in

Europe. It is also established in Asia. The only previous U.S. infestation of the beetle occurred in New

Jersey in 1913.

The beetle was probably introduced into the

United States in 1992 by foreign ships carrying beetle-infested wood as dunnage. (Dunnage is packing

material used to protect a ship’s cargo from damage

during transport.) Since the 1992 introduction, pine

shoot beetle has been detected in 11 northeastern

States. Quarantines have been enacted in these

States to restrict the movement of regulated articles

in order to prevent the artificial spread of the beetle.

APHIS Involvement

In cooperation with State officials, APHIS is

requiring the inspection of cut pine Christmas trees,

pine nursery stock, pine logs, stumps, and lumber

with bark attached, and pine bark mulch before these

regulated articles can move out of quarantined areas.

(Lumber and logs without bark attached are not regulated.)

Additionally, APHIS and cooperating officials are

conducting detection surveys for the pest. State and

Federal scientists are working with the affected

industries to develop appropriate control and management strategies.

Factsheet

 	
  
	 	 

APHIS
Two methods to detect the beetle in noninfested

areas are visual surveys and traps baited with attractants. Visual surveys take place primarily in the summer and fall when adult beetles feed in the pine

shoots. Traps attract and capture beetles in late winter and early spring while they fly from their overwintering sites to mating and egg-laying sites.

To manage pine shoot beetle populations in

Christmas tree farms and nursery stock plantations,

APHIS implemented a State-managed compliance

management program. Using an intricate series of

management protocols throughout the production

cycle of the plants, this integrated pest management

program reduces pine shoot beetle populations in

host plants and growing areas. The program’s 

protocols include sanitation practices to remove

breeding material from the fields, chemical controls to

reduce adult shoot feeding, and visual and trap surveys to monitor population levels.

Additional Information

For more information about the pine shoot beetle,

contact one of the following:

1. Your State’s regulatory officials, usually listed 

under department of agriculture, plant protection 

or regulatory division, in the State government 

section of your telephone directory.

2. A U.S. Federal regulatory official, listed in the 

Federal Government section of your telephone 

directory under USDA, APHIS, Plant Protection 

and Quarantine. If you have access to the 

Internet, point your browser to 

http://www.aphis.usda.gov/ppq and click on 

“directories” for a list of offices.

United States Department of Agriculture • Animal and Plant Health Inspection Service • Safeguarding American Agriculture

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