Preventing mammal damage to trees and woodland

The following tables show

A. A summary of options available for protecting trees from certain species of mammals
B. An assessment of the advantages and disadvantages for each method

Table A: Summary of options for tree protection

  Barriers Preferred control
Tree guards Fencing Electric
fencing
Chemical
repellents
Shooting Gassing/
poisoning
Trapping/
snaring
Field vole

yes

no

no

?

no

no

no

Bank vole

yes

no

no

no

no

no

no

Grey squirrel

no*

no

no

?

no

yes

yes

Rabbit

yes

yes

no

?

?

yes

?

Hare

yes

yes

no

?

?

no

no

Deer

yes

yes

?

?

yes

no

no

Sheep & goats

?

yes

yes

no

no

no

no

Cattle & ponies

no

yes

yes

no

no

no

no

* Isolated specimen trees can have smooth collars fitted.

Table B: Assessment of protection methods

Method Advantages Disadvantages
Tree guards
  • Cost effective for small areas
  • Can protect trees from herbicide damage
  • Can make trees easier to locate
  • Do not present a barrier to public access
  • Do not prevent positive herbivore impacts on ground vegetation
  • Can provide an early boost to growth
  • Do not protect other elements of the woodland ecosystem
  • Are costly for large areas
  • Require regular inspection, maintenance and often eventual removal
  • Are generally not reusable
  • Taller guards can be unstable and cause damage to trees and stem weakness in windy situations
  • Can be unsightly and attract vandalism
Fencing
  • Cost effective for large areas and high stocking densities
  • Often less visually intrusive than individual tree protection
  • Offers protection for natural regeneration and other woodland vegetation
  • Expensive for small areas
  • Reduces accessibility to woodland users
  • A breach can put whole planted area at risk
  • May prevent beneficial herbivore impacts
  • Some reduction of animal numbers may also be necessary when populations are high
Electric fencing
  • Low capital cost
  • Reusable
  • Can be effective in protecting short tern regeneration e.g. coppice
  • Generally reliable for domestic stock only
  • Dependent on intensive checking and maintenance
  • Requires reliable power source and earthing; breach or loss of power renders the whole fence-line ineffective
Chemical repellents
  • Useful emergency measure for immediate and over-winter protection of small areas
  • Expensive for large areas and where repeat applications are necessary
  • Current repellents offer limited duration of protection and do not protect growth occurring after treatment
Deer - shooting
  • Limits deer damage whilst maintaining positive impacts
  • Recognises deer as a part of forest biodiversity, as a recreational resource, as a tool for habitat management, and as a potential source of income
  • Requires time, experience, planning and long-term commitment to implement
  • Requires co-operation with neighbours if used in small woodlands
  • Public safety considerations may limit potential to cull
Grey squirrels -poisoning
  • The most effective method currently available, particularly in terms of labour requirement
  • Use of a hazardous mammalian toxin in the environment
Grey squirrels -multi-capture traps
  • Easy to site and set; may be used even where red squirrels are resident
  • High capital cost and labour requirement
Rabbits - gassing
  • The most effective method of rabbit control
  • Requires properly trained and equipped personnel
Rabbits - cage traps
  • Non-target species can be released unharmed
  • Does not require access to burrow systems
  • Useful for removal of rabbits from within fenced areas
  • Unsuitable for removing substantial numbers of rabbits
Rabbits - box traps
  • Can catch substantial numbers of rabbits
  • Useful for removal of rabbits from within fenced areas and for maintaining good relations with neighbours
  • High capital cost
       

What's of interest

Further reading
Several Forestry Commission publications covering mammal management in more detail. Some are available for downloading.

Related pages

Useful sites