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David studied Biology and Applicable Mathematics at University of Derby and graduated in 1996. He came to Forest Research in 1997 as a D.Phil. student, where he worked on his thesis ‘The impact of defoliating insects on Sitka spruce’, and graduated in 2001. He started work at Forest Research in 2001 as a Forest Entomologist and his current research interests include the ecology of bark-beetles and other wood boring insects, the impact of defoliating insects, and monitoring the spread and impact of new invasive insect species.

  • Bark-beetles and other wood-boring insects
  • Influence of climate change on forest insects
  • Defoliating insects and impacts on tree growth
  • Biosecurity.


  • Member of the Royal Entomological Society.
Tree health

Forest Research

Alice Holt Lodge


Surrey GU10 4LH


Related Research


Oak lace bug in Europe (OLBIE): Evaluation of the pest status in Europe and development of survey, control and management strategies

This Euphresco project will focus on the oak lace bug (Corythucha arcuata), with an emphasis on evaluating its pest status in Europe and assessing survey, control and management strategies.

Status current


Climate change impacts on insect pests associated with Sitka spruce

This project is investigating the potential impact that a changing climate may have on the insect pests associated with the UK’s most important and widely planted conifer tree species Sitka spruce.

Status current
Use of pheromone traps to monitor oak processionary moth

This project is carrying out experimental trials to improve and standardise the use of pheromone traps for monitoring populations of oak processionary moth.

Related Publications


[Archive] Forest nursery herbicides

Information is given on the use of forest nursery herbicides. Much of this information is based on the results of Forestry Commission experiments. A brief description of the types of herbicides is given followed by information on the various herbicides which can be used at the different stages of forest nursery stock production. This publication […]


Other Research

Peer reviewed journal articles

Journal papers

Straw, N.A., Fielding, N.J., Tilbury, C., Williams, D.T. and T. Cull (2016) History and development of an isolated outbreak of Asian longhorn beetle Anoplophora glabripennis (Coleoptera: Cerambycidae) in southern England. Agricultural and Forest Entomology 18, 280-293.

Straw, N.A., Tilbury, C., Fielding, N.J., Williams, D.T. and T. Cull (2015) Timing and duration of the life cycle of Asian longhorn beetle Anoplophora glabripennis (Coleoptera: Cerambycidae) in southern England. Agricultural and Forest Entomology 17, 400-411.

Williams, D.T., Cull, T., Straw, N. and G. Jonusas (2015) The use of pheromone traps for the early detection and monitoring of oak processionary moth (Thaumetopoea processionea L.). Invasive Insects and Trees: Detection, Management and Policy Conference, University of Hull, UK. 19-20 February 2015.

Straw, N.A., Fielding, N.J., Tilbury, C., Williams, D.T. and D. Inward (2015) Host plant selection and resource utilisation by Asian longhorn beetle Anoplophora glabripennis (Coleoptera: Cerambycidae) in southern England. Forestry 88, 84-95.

Straw, N., Fielding, N., Tilbury, C., Williams, D. and D. Inward (2014) Asian longhorn beetle outbreak in the UK. Poster presented at Defra Plant Health Stakeholder Summit, 20th January 2014. Emmanuel Centre, London.

Straw, N., Williams, D., Kulinich, O. & Gninenko, Y. (2013) Distribution, impact and rate of spread of emerald ash borer Agrilus planipennis (Coleoptera: Buprestidae) in the Moscow region of Russia. Forestry 86, 515–522.

Straw, N.A. and D.T. Williams (2013) Impact of the leaf miner Cameraria ohridella (Lepidoptera: Gracillariidae) and bleeding canker disease on horse-chestnut: direst effects and interaction. Agricultural and Forest Entomology 15, 321-333.

Williams, D.T., Straw, N., Townsend, M., Wilkinson, A.S. and Mullins, A. (2013) Monitoring oak processionary moth, Thaumetopoea processionea L. (Lepidoptera: Thaumetopoeidae) using pheromone traps: The influence of pheromone lure source, trap design and height above the ground on capture rates. Agricultural and Forest Entomology 15, 126-134.

Straw, N., Fielding, N., Green, G., Price, J. and Williams, D. (2011). Defoliation and growth relationships for mid-rotation Sitka spruce attacked by the green spruce aphid, Elatobium abietinum (Walker)(Homoptera:Aphididae). Forest Ecology and Management 262, 1223-1235.

Harmer, R., Straw, N. and Williams, D. (2011). Boar, bluebells and beetles. Quarterly Journal of Forestry 105, 195-202.

Straw, N.A., Williams, D.T. and Green, G. (2011). Influence of Sticky Trap Color and Height Above Ground on Capture of Alate Elatobium abietinum (Hemiptera: Aphididae) in Sitka Spruce Plantations. Environmental Entomology 40, 120-125.

Tilbury, C., Williams, D., Jukes, M. and Straw, N. (2010). The re-establishment of gypsy moth (Lymantria dispar (Linn.)) in the UK. Atropos 40, 36-42.

Straw, N., Williams, D. & M. Jukes (2008). Insect Diversity and Continuous Cover Forestry. Ecotype 42, p. 3.

Straw, N.A., Green, G. and Williams, D.T. (2007). Dieback and recovery in poplar and attack by the hornet clearwing moth, Sesia apiformis (Clerk) (Lepidoptera: Sesiidae). Bulletin of Entomological Research 97, 555-567.

Williams, D.T. and Evans, H.F. (2007). A preliminary investigation into the potential use of a hydrocyclone to concentrate entomopathogenic nematodes from suspension. Biocontrol Science and Technology 17, 155-169.

Williams, D.T., Straw, N.A., and Day, K.R. (2005). Performance of the green spruce aphid, Elatobium abietinum (Walker) on previously defoliated Sitka spruce. Agricultural & Forest Entomology 7: 95-105

Williams, D.T., Straw, N.A., and Day, K.R. (2003). Defoliation of Sitka spruce by the European spruce sawfly, Gilpinia hercyniae (Hartig): a retrospective analysis using the needle trace method. Agricultural & Forest Entomology 5, 235-245.

Conference proceedings and posters

Mayle, B., Harmer, R., Kiewitt, A., Peace, A., Straw, N., Williams, D. and Upson, M. (2011). The impacts of feral boar on woodland flora and fauna in Great Britain. Julius-Kühn-Archiv 432, 219-220. 8th European Vertebrate Pest Management Conference. 26-30 September 2011, Berlin, Germany.

Williams, D.T., Straw, N., Jukes, M., Fielding, N. and Price, J. (2011). Influence of forest management on bark-beetle (Scolytidae) populations inhabiting Sitka spruce plantations in Wales, UK. IUFRO WP.7.03.05 – Ecology and Management of Bark and Wood Boring Insects. Novel risks with bark and wood boring insects in broadleaved and conifer forests. 7-9 September 2011, Sopron, Hungary.

Upson, M., Williams, D., Straw, N., Harmer, R. & Kiewitt, A. (2010). Impacts of feral boar on woodland flora and invertebrates. 8th International Symposium on Wild Boar & Other Suids, York.

Straw, N., Williams, D. and G. Green (2009). Conifer aphids see red? Royal Entomological Society, Aphid Special Interest Group Meeting, Rothamsted, 16th November 2009.

Barsoum, N., Williams, D., Straw, M. Jukes, R., Johnson, M. Bidartondo, R., Kiewitt, A. & Ibrahim, R. (2009). Consequences of increased stand structural complexity for floral diversity and the prevalence of insect pests in Sitka spruce (Picea sitchensis) stands. Adapting Forest Management to Maintain the Environmental Services: Carbon Sequestration, Biodiversity and Water. Koli National park, Finland 21-24 September 2009.

Williams, D.T., Straw, N., Jukes, M., Fielding, N. and J. Price (2009). Impact and Diversity of Insects in Alternative Silvicultural Systems. 2nd Northern Coleopterists Meeting, Manchester Natural History Museum, Manchester, 26 September 2009.

Williams, D.T., Straw, N.A. & Day K.R. (2000). Impact of European spruce sawfly (Gilpinia hercyniae) on Sitka spruce. The Fourth National Meeting of the Royal Entomological Society. Liverpool Hope University College, 14-15 September 2000.


Williams, D. T. (2013) Scientific report on emerald ash borer (Agrilus planipennis Fairmaire) in Russia. Short Term Scientific Report for EU COST Action FP1002 – Pathway evaluation and pest risk management in transport (PERMIT). Ref. code: COST-STSM-ECOST-STSM-FP1002-070713-032618.

Straw, N., Williams, D. and C. Tilbury (2013) Monitoring the oak processionary moth with pheromone traps. Forestry Commission Practice Note FCPN020. July 2013.

Williams, D.T., Straw, N., Fielding, N. and Price, J. (2012) Do forest management systems influence the abundance and diversity of the natural enemies associated with the green spruce aphid (Elatobium abietinum) in Sitka spruce plantations in Wales, UK. Joint IUFRO WP.7.03.10 – Methodology of forest insect and disease survey, and IUFRO WP.7.03.06 – Integrated management of forest defoliating insects, working party meeting, Palanga, Lithuania, 10-14 September 2012.

Williams, D.T., Straw, N. and Townsend, M. (2011) Variables influential in determining trap capture efficiency of the oak processionary moth (Thaumetopoea processionea L. Oak Processionary Moth Stakeholders meeting, Westminster, London. 2nd November 2011.


Williams, D. and N. Straw (2013) Oak processionary moth (Thaumetopoea processionea), Asian longhorn beetle (Anoplophora glabripennis) and Emerald ash borer (Agrilus planipennis). Seminar presented at All-Russian Center of Plant Quarantine, Bykovo, Moscow Region, Russia. July 2013.