April Armstrong


Previous projects

Delivering resilient forests - Managing biotic threats - Advice and support for pest and disease management

Advisory pathologist for the Tree Health Diagnostic and Advisory Service

  • Receiving enquiries via TreeAlert
  • Diagnosing the causes of ill health and disease in forest and amenity trees through laboratory analysis and site visits
  • Providing advice to enquirers in the public and private sectors on tree health.
  • Providing up to date information on current and future pests and diseases to inform tree health management.
  • Providing training for Observatree and working with volunteers

Understanding Biotic Threats - Surveillance and detection

Developing and applying techniques to aid the surveillance and detection of fungal pathogens with a particular focus on trapping and quantifying spore inoculum of the ash dieback pathogen Hymenoscyphus fraxineus. Developing a method for spore DNA extraction and quantification using qPCR.

Assessing the epidemiology of Phytophthora austrocedri infecting Juniperus communis berries as a potential route of disease transmission.

Distribution, morphological characterisation and growth rate of Phytophthora austrocedri

See publication list

Anthropogenic influences on the transmission of Phytophthora ramorum via mountain biking and walking in Scottish forests

FR supervisor of BSc Honours project in conjunction with Stirling University


Related publications

Peer reviewed papers

Metabarcoding reveals a high diversity of woody host-associated Phytophthora spp. in soils at public gardens and amenity woodlands in Britain

A study of Phytophthora diversity in public gardens and amenity woodlands through the use of metabarcoding of soil samples.


  • Pests and diseases
Peer reviewed papers


  • Pests and diseases

Peer reviewed journal publications

Henricot, B., Pérez-Sierra, A., Armstrong, A., Sharp, P. M., Green, S. 2017. Morphological and genetic analyses of the invasive forest pathogen Phytophthora austrocedri reveal two clonal lineages colonised Britain and Argentina from a common ancestral population. Phytopathology (In Press)

Kaczmarek, M., Piotrowska, M.J., Fountaine, J.M., Gorniak, K., McGrann, G.R.D., Armstrong, A., Wright, K.M., Newton, A.C. and Havis, N.D. (2016). Infection strategy of Ramularia collo‐cygni and development of ramularia leaf spot on barley and alternative graminaceous hosts. Plant Pathology.

Green, S., MacAskill, G.A., Dun, H., Armstrong, A.C., Henricot, B. (2016). First report of Phytophthora austrocedri infecting Nootka cypress in Britain New Disease Reports 33, 21. [http://dx.doi.org/10.5197/j.2044-88.2016.033.021]

Green, S., Elliot, M., Armstrong, A. and Hendry, S.J. (2015). Phytophthora austrocedri emerges as a serious threat to juniper (Juniperus communis) in Britain. Plant Pathology, 64(2), pp.456-466.

Books, book chapters and published conference proceedings

Green, S., Elliot, M., Armstrong, A., Hendry, S.J. (2015). Phytophthora austrocedri emerges as a serious threat to juniper (Juniperus communis) in Britain. Proceedings of the 7th Meeting of IUFRO WP 7.02.09 Phytophthora in Forests & Natural Ecosystems, Esquel, Argentina November 10-14th 2014. In Press.

Elliot, M., Schlenzig, A.,Harris, C.M.,  Meagher, T.R., Green, S. (2015). An improved method for the qPCR detection of three Phytophthora spp. in forest and woodland soils in northern Britain. Forest Pathology 45, 537-539. (Acknowledged contribution)

Outreach, newsletter and trade publications

Armstrong, A. (2014) An ecological assessment of Ramularia collol-cygni infection in different temperate plant species. BSPP News.