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English hawthorn

English hawthorn

English hawthorn

(Crataegus monogyna)

Priority: -  Contain

Tags: Agricultural | Terrestrial

Identification and Reproduction

Identification

  • English hawthorn is a deciduous shrub or small tree.
  • It grows up to ten metres tall, and is scaly and prickly.
  • It has broad, alternately arranged leaves. They are ovate to triangular and three to seven lobed, appearing paw-like. 

  • New stems will appear reddish-brown and are often covered in thorns
  • Its flowers have pink to white petals, and grow in clusters similar to cherry blossoms.



Reproduction

  • It will produce berries after ten years, and these seeds can be spread by birds, animals, soil, and water.
  • Berries will stay on the tree over the winter.
  • This plant may also spread vegetatively.

Habitat & Ecology

  • It prefers moist soil, such as woodlands, grasslands, and riparian areas.
  • It is drought-tolerant and somewhat shade-tolerant.

Impacts

Social: 

Once used to create hedgerows to contain livestock, it has now invaded pastures and grasslands. 

Ecological: 

  • It is capable of hybridizing with the native hawthorn species, altering the gene pool. 
  • Also disrupts the native pollination cycle. 
  • It grows into thickets within forests, blocking animal movement and crowding out native plants.
  • English hawthorn also may grow very "bushy" and will evidently shade out any lower ground vegetation.

Management

Mechanical/Manual Control:

  • Since English hawthorn is covered in thorns, ensure you are wearing proper protective clothing and gloves. 
  • Removal is most effective when plants are immature and small. Avoid removing plants that bear fruit. 
  • Seedlings can be hand-pulled. 
  • Dig up roots and remove any cut fragments as these can resprout. 

Chemical Control: 

  • After tree removal herbicide application to the cut stems may be effective. 

Resources

Download the Garry Oak Ecosystem Recovery Team's handbook for English Hawthorn here. 

King County is a good resource for English hawthorn identification and control measures. Note that this is a US resource, Canadian guidelines and regulations may differ. Be sure to read product and chemical instuctions prior to use. 

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