The Peach Tree Borer, scientifically known as Synanthedon exitiosa, is a notorious pest for peach and nectarine trees, as well as other stone fruits like apricot, cherry, and plum. This destructive insect is native to North America and has become a major concern for fruit growers in the region. The larvae of peach tree borers target the roots and lower trunks of their host trees, feeding on the growing tissue and inner bark, causing significant damage that can potentially lead to the death of younger trees.
Adult peach tree borers emerge between July and August, with females laying up to 500 eggs on tree trunks or in the soil near the tree trunk. Once the eggs hatch, the grub-like larvae begin their destructive journey, tunneling under the bark at the tree’s base and on larger roots. Damage caused by these pests can result in reduced fruit production, weaken the trees, and, in severe cases, kill the tree outright.
Effective management and control of peach tree borers are crucial to maintaining the health and productivity of fruit orchards. Some commonly used methods include regular monitoring, trapping, and the use of chemical control measures. By being proactive and vigilant, it is possible to minimize the damage caused by these menacing pests and ensure a healthy and fruitful harvest.
Peach Tree Borer Identification
Synanthedon Exitiosa
The Peach Tree Borer (Synanthedon exitiosa) is a significant pest that typically targets peach and nectarine trees but can also attack apricot, cherry, and plum trees1. This insect is native to North America and can be found throughout the United States and Canada2.
Moths and Wasps
Peach Tree Borers belong to the clearwing moth family. Although they resemble small wasps, they are actually moths2.
Male and Female Peachtree Borers
- Male Peach Tree Borers have four narrow yellow bands on their abdomen and clear wings, making them look like small wasps2.
- Female Peach Tree Borers are dark blue with two distinct orange bands on their abdomen, and opaque front wings2.
Here is a comparison table for easy reference:
| Male Peach Tree Borer | Female Peach Tree Borer | |
|---|---|---|
| Color | Blue | Dark Blue |
| Abdomen | 4 Yellow Bands | 2 Orange Bands |
| Wing Type | Clear | Opaque Front Wings |
Life Cycle and Biology
Eggs and Larval Stage
- Eggs: Peach tree borers lay up to 500 eggs on tree trunks, in cracks, under bark scales, and in soil near tree trunks during July and August1.
- Larvae: After hatching, they tunnel into roots and lower trunks, feeding on growing tissue and inner bark2.
Pupal Stage
- Overwinter: Larvae partly grow in their burrow beneath tree bark during winter1.
- Pupation: In spring, they complete their growth, construct a cocoon under the bark at or near soil level, and pupate1.
Adult Stage
- Transformation: Adults emerge 17 to 25 days after pupation1.
- Moths: Adult peach tree borers resemble paper wasps, with bluish-black females featuring an orange band on the abdomen3.
Damage and Infestation Detection
Soil Line and Lower Trunk
Peach Tree Borer primarily attacks the soil line and lower trunk area of peach, nectarine, cherry, plum, and apricot trees1. The larvae cause damage by tunneling into the roots and lower trunks, feeding on the growing tissue and inner bark2.
- Features:
- Infestations often around the soil line and below
- Larval damage to roots and lower trunks
Examples of infestation signs include holes, sawdust-like frass, and girdling on the roots and trunks2.
Bark Wounds and Oozing
Bark wounds can be a sign of Peach Tree Borer infestation. Adult moths lay eggs on tree trunks, in cracks or under bark scales, and in soil near the tree trunk1. When larvae feed on the inner bark, this can create wounds on the tree bark.
- Characteristics:
- Wounds on tree bark
- Larval feeding may cause oozing sap or gum
Oozing sap is another symptom to look for, as the larvae tunnel into sapwood3. If you notice oozing or sap leakage from wounds on the bark, it might indicate a Peach Tree Borer infestation.
Gum and Sapwood
The main symptom of Peach Tree Borer infestation in the sapwood and gum area is the presence of gummosis4. Gummosis refers to a tree’s production of gum or sap in response to stress, such as Peach Tree Borer damage.
- Features:
- Gummosis near damaged areas
- Presence of gum or sap around wounds
Damage to sapwood can be severe in young trees2. If you spot gum or sap around wounds on branches or the tree trunk, it might be a sign of a Peach Tree Borer infestation4.
| Infestation Indicator | Symptoms |
|---|---|
| Soil Line | Holes, frass, girdling at soil line |
| Bark Wounds | Wounds on bark, oozing sap |
| Gum and Sapwood | Gummosis, sap around wounds, perfumes5 |
Monitoring and Control Methods
Pheromone Traps
Pheromone traps are an effective method for monitoring peach tree borer populations. They contain synthetically produced pheromones to attract male moths, helping to estimate the population size and the best timing for control measures. Key benefits include:
- Reducing reliance on chemical treatments
- Being non-toxic and eco-friendly
A downside of pheromone traps is that they only capture male moths, which may not reflect the actual population of larvae damaging the tree.
Mating Disruption
Mating disruption involves using pheromones to confuse male moths, impairing their ability to find females. This method has several advantages:
- Eco-friendly and non-toxic
- Compatible with Integrated Pest Management (IPM) strategies
- Reducing the need for chemical treatments
However, initial costs can be high, and its effectiveness may be limited in areas with high borer populations or in small orchards.
Chemical Treatments
Chemical treatments, such as insecticides, can provide effective control of peach tree borer. Two common insecticides include permethrin and carbaryl. These treatments should be applied when larvae are active and before they enter the tree to cause damage.
| Insecticide | Pros | Cons |
|---|---|---|
| Permethrin | Effective control; readily available | May harm beneficial insects; regular reapplication is required |
| Carbaryl | Wide range of target pests; longer residual activity | May harm beneficial insects; possible human health concerns |
When using chemical treatments, it’s essential to apply them correctly and within the recommended guidelines to minimize the risk to beneficial insects and the environment.
Remember, maintaining healthy trees with proper pruning and watering can also help prevent infestations by making them less attractive to peach tree borers.
Bug Control Recommendation Tool
Preventing Peach Tree Borer Infestations
Tree Selection and Care
Selecting and properly caring for peach trees can help prevent damage from the Peach Tree Borer.
- Opt for resistant tree varieties, where possible.
- Ensure proper soil, water, and nutrient conditions for healthy tree growth.
- Prune damaged and diseased branches to help maintain tree health.
Tree Trunk Protection
Taking steps to protect tree trunks minimizes the opportunity for borers to infest.
- Apply a 50:50 latex paint solution to lower 12 inches of trunk (USU Extension).
- Inspect tree trunks regularly for signs of infestation, such as wounds or sawdust-like debris.
Cultural Practices
Preventive cultural practices can limit Peach Tree Borer populations.
- Monitor trees using pheromone traps to detect adult borer presence and determine an appropriate time to apply controls.
- Reduce overwintering larvae by removing and disposing of infested wood and debris.
- Minimize mechanical injury to the tree trunks.
Impact on Stone Fruit Trees
Peaches and Nectarines
The peach tree borer is a primary pest of peach and nectarine trees. The larvae feed on growing tissue and inner bark, leading to reduced crop bearing capacity due to lack of nutrient uptake1. This can result in wilt, stunted growth, and even tree death.
Cherries
Cherry trees are also susceptible to peach tree borer infestations. The grub-like larvae can feed on the base and larger roots of the cherry trees, undermining the tree’s health2.
Apricots
Peach tree borer attacks apricot trees as well. The larvae can bore underneath the bark, causing serious damage to the tree.
Plums
Plum trees, including flowering plum, can suffer from peach tree borer infestations. The insect pest targets the roots and the trunk’s base in plum trees, putting them at risk for a weakened structure and potential death3.
In summary, the peach tree borer impacts various stone fruit trees, including:
- Peaches
- Nectarines
- Cherries
- Apricots
- Plums
Common signs of peach tree borer infestation include:
- Wilt
- Stunted growth
- Tree death
Footnotes
- (https://extension.psu.edu/tree-fruit-insect-pest-peachtree-borer) ↩ ↩2 ↩3 ↩4 ↩5 ↩6 ↩7 ↩8
- (https://content.ces.ncsu.edu/peachtree-borer) ↩ ↩2 ↩3 ↩4 ↩5 ↩6 ↩7 ↩8 ↩9
- NC State Extension Publications ↩ ↩2 ↩3
- Colorado State University Extension ↩ ↩2
- Washington State University Tree Fruit ↩
4 Comments. Leave new
Just saw one for the first time. I live in SW Michigan and I found one burrowing in my shredded bark.
There is sap oozing from the base of our plum trees and we are wondering if the Peach Tree Borer has made it to California, or if a relative may be boring in the trunk of our trees.
Strange bug…
Took a video in Denver of the mating ritual. Yes I was dumbfounded while capturing the moment so ignore the audio, 🙂