An Integrated Approach

Bartlett Tree Experts uses an integrated approach to managing insects and diseases that begins with maintaining plant health using sound cultural practices including pruning and creating optimal soil conditions for plant growth. Periodic inspections are essential to detect pest infestations before they reach damaging levels. Bartlett arborists are trained to recognize beneficial insects that will help naturally suppress pest populations, and we also release beneficials to augment existing populations. When treatments are necessary, Bartlett can apply organic and naturally based materials and reduced-risk products that provide effective pest suppression while protecting people and the environment.
Top-10 Insects
Hundreds of insect species damage leaves, stems, and branches; roots; and flowers and fruit of landscape plants. But not all insects on trees and shrubs are damaging. Some are beneficial and may help pollinate flowers or could be predators or parasites on insects that damage plants. Bartlett arborists are trained to correctly identify these beneficial insects and mites and can devise effective management programmes that protect landscape plants from serious damage while conserving beneficial organisms.
Top ten insect and arthropod pests that threaten or damage landscape plants in Great Britain and Ireland:
- Aphids and Whiteflies
- Woolly Aphids
- Brown-Tail Moth
- Conifer Shoot Miner
- Horse Chestnut Leaf Miner
- Flea Beetles
- Leafhoppers
- Oak Processionary Moth
- Spider Mites
- Scale Insects
Top-10 Diseases
Diseases are abnormalities in trees and shrubs caused by microorganisms such as fungi and bacteria and by environmental stress such as drought, temperature extremes, and air pollution. Diseases are often difficult to diagnosis as different causal agents can produce similar symptoms. Accurate diagnosis is essential to developing effective treatment programmes. Bartlett operates a modern diagnostic laboratory to support pest management services to ensure accurate identification and treatment of plant problems.
Top ten diseases that threaten or damage landscape plants in Great Britain and Ireland:
- Phytophthora Root Rot
- Bacterial Bleeding Canker
- Chalara Ash Dieback
- Apple Scab
- Anthracnose
- Leaf Blotch
- Fire Blight
- Massaria (London Plane)
- Honey Fungus
- Powdery Mildew

Horse Chestnut Leaf Miner
A widespread, damaging pest of horse chestnut, the larvae tunnel into leaves resulting in brown patches on the leaf surface.

Oak Processionary Moth
This defoliating pest is found in many boroughs of London. Contact with OPM caterpillars can result in health issues so removal is always recommended.

Ash Dieback
Chalara ash dieback is caused by a fungus that results in premature leaf loss and crown dieback in ash trees.
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We specialise in a variety of services. Our aim is to deliver the top level of customer service based on your requests.
- There is a web-type coating on the limbs of one of our Valley Oak trees. It looks like a sleeve of webbing, thin and solid, starting at the trunk and going up several limbs. We have four trees spread out, and only one has this issue. It has been there for about two weeks and is starting to get less. What might it be, and is it bad for the tree?
- My magnolia tree has scale. What can be done?
- My magnolia tree has a secretion. The secretion attracts mostly black wasps, but other insects are also attracted to it. The tree appears to be dying a slow death. The secretion catches fire when exposed to a lit match. The secretion stains anything it falls on. The secretion is sticky to the touch. Can you diagnose the problem and recommend a remedy?
- My tree is in terrible shape. The leaves have what looks like a lot of black mold on them. One side of the tree has lost all of its leaves. My landscaper planted this tree last year and I'm wondering if the sprinkler is watering it too much. This tree looks like it could die.
- My Hemlock Tree is losing foliage. The branches are bare of needles, except for top of tree. There is new growth but bare branches still remain. Can the tree be salvaged?
- I have a ten year old lemon tree. Recently, the tree is experiencing yellowing of leaves and a lot of early leaf drop. I get flood irrigation twice a month and fertilize it with citrus fertiliser three times per year. What is happening to this tree?
- We recently had our maple tree pruned. It now has spots all over the leaves. Can you tell me what is causing this and what treatment options there are?
- What is your expertise regarding the Emerald Ash borer infestation?
- My jatropa tree has rust and sticky white stuff attached to the leaves and branches. Also, the blooms and leaves are shriveled. What can I do to save this tree?
- Is Arborbiotic injected into the root collar or trunk flair? I understand that Arborbiotic injections may not completely control fire blight on a Callery 'Redspire' pear (Pyrus calleryana) even with a fertilisation programme using Forti Phite plus calcium and the tree will need to be injected every year. I also understand the branches that are infected with fire blight will need to be pruned six inches back from the infection and pruning tools sterilized after each pruning cut.
- I have apple and pear trees. Every year I get worms in my fruit, no matter the spray or schedule and the labels on the sprays are confusing. What can I do?