Staff
Ian Willoughby
BSc, MBA, PhD, FICFor
BSc, MBA, PhD, FICFor
As a Principal Silviculturist, Ian has particular research expertise in integrated forest vegetation management and early silviculture. In both cases his ethos is to deliver clear, practical solutions for forest managers, based on undertaking high quality peer reviewed science.
Ian’s research on forest vegetation management covers all silvicultural systems and includes plant competition, the use of pesticides as control measures for dealing with invasive pests, diseases and weeds, alternatives to pesticides and pesticide reduction, and developing integrated solutions for managing invasive vegetation.
Ian’s research on early silviculture focuses on adapting forest regeneration to increase resilience to climate change and biotic threats.
Ian obtained a BSc (Honours) in forestry from the University of Wales at Bangor in 1991, an AMBA accredited Master’s Degree in Business Administration (MBA) from the Open University in 1999 and a PhD in forestry from the University of Wales at Bangor in 2010. He joined the Forestry Commission in 1991 as a District Forester, has worked for Forest Research since 1992, as well as spending time in management roles in various other parts of the Forestry Commission.
Alice Holt
Alice Holt Lodge
Wrecclesham
Farnham
Surrey
This research aims to determine the practicality, durability, and efficacy of non-plastic biodegradable tree shelters and other tree protection methods, as alternatives to using tree shelters made from conventional plastics.
Resilient forests are important if our trees are to cope better with changing environmental conditions and threats from pests and diseases. This page provides information on the publications produced as part of Forest Research's 'Delivering Resilient Forests' programme of research.
Ecoplugs containing glyphosate can be an effective means of killing standing trees, and preventing regrowth from cut rhododendron stumps.
Gaultheria shallon can be effectively controlled by the herbicides picloram, triclopyr or glyphosate if they are applied at the correct time of year.
Adapting forest regeneration to increase resilience to climate change and biotic threats, whilst maintaining productivity.
Aims to reduce dependence on herbicides in Europe’s forests by sharing best practice and encouraging collaboration across the EU
Practical solutions for woodland establishment and regeneration in lowland situations
Best methods for restoring & expanding major native woodland types in upland Britain
Non-hazardous rapeseed oil spray adjuvants do not improve the rainfastness or effectiveness of glyphosate for Rhododendron ponticum shrub control.
A study of chemical runoff following the use of acetamiprid as a pre-treatment and top-up spray to prevent damage from the large pine weevil (Hylobius abietis L.) to young trees was undertaken at a restock site in mid-Wales. The site was specifically selected to pose a high risk of chemical runoff, being a high elevation, […]
The pearl-bordered fritillary (Boloria euphrosyne) is a resident UK butterfly which is in decline, partly because grasses can outcompete its preferred food plant, common dog-violet (Viola riviniana). We therefore investigated whether using graminicides could help to enhance the habitat quality of a violet-rich butterfly ride. Applications of 1.5 kg a.i. ha-1 propyzamide or 0.45 kg a.i. ha-1 cycloxydim both reduced grass cover and were associated with an increase in violet plants. Our work suggests that enhancing pearl-bordered fritillary habitat may not always be possible through herbicide use alone, but cycloxydim may have a useful role in helping to reduce competition from grasses.
Results from EU COST Action E47 to help forest managers reduce their dependence on using herbicides in Europe’s forests. Edited by Ian Willoughby (Forest Research), Philippe Balandier, Niclas Scott Bentsen, Nick McCarthy and Jenny Claridge (Forest Research). Related pages Integrated forest vegetation management
By Ian Willoughby. Related pages Integrated forest vegetation management
In UK forestry, the synthetic pyrethroid insecticides alpha-cypermethrin and cypermethrin have been used for many years to provide protection for young trees planted on restock sites from damage by the large pine weevil, Hylobius abietis L. However, concerns over the toxicity of these insecticides to aquatic life if misused has led to a search for alternative forms of protection. This paper describes a detailed programme of efficacy experiments undertaken between 2009 and 2014 to find replacements for these products. Over 50 combinations of chemical and non-chemical approaches were tested on 16 different sites.
Can direct seeding be used to enhance the restoration of native species to conifer plantations on ancient woodland sites?
The herbicide cycloxydim is an effective alternative to propyzamide or glyphosate for the control of the forest grass weeds Molinia caerulea, Calamagrostis epigejos, Deschampsia flexuosa and Holcus lanatus.
Acetamiprid, chlorantraniliprole, and in some situations the physical barriers MultiPro® or Kvaae® wax, can be alternatives to traditional synthetic pyrethroid insecticides for the protection of young conifers from damage by the large pine weevil Hylobius abietis L.
Good weed control is essential for quality Christmas tree production. Herbicides are usually the most cost-effective way of achieving this. Two principal categories of Christmas tree production can be identified: production in forest plantations and specialist horticultural production. For these two situations, suitable candidate herbicides are identified, and guidance on their safe and effective use […]
Information is given on the use of herbicides in farm woodland and short rotation coppice. Recommendations are given for suitable herbicides for a range of crop and weed species. Approval status, approved products, crop tolerance, weed susceptibility and herbicide mixtures are discussed. A lengthy appendix lists notices of approval for proprietary products. This publication is […]
A comprehensive account of chemical weed control techniques for use in forestry. Covers pesticide legislation, safety precautions and good working practices, herbicides for use against specific weed vegetation types, farm forestry weed control, protective clothing and personal equipment, application equipment and output guides, lists of herbicides and manufacturers, sources of advice, and an index of […]
Parratt, M. J., Willoughby, I. H. and Forster. J. (2022) The potential of the selective graminicides cycloxidim and propyzamide as habitat improvement tools for the pearl-bordered fritillary butterfly. Quarterly Journal of Forestry 116 (3), 166-172.
Willoughby, I.H., Stokes, V.J., Forster, J. and Harmer, R. (2020). Can direct seeding be used to enhance the restoration of native species to conifer plantations on ancient woodland sites? Scottish Forestry 74 (3), 20-28. (For a PDF copy of this paper please contact ian.willoughby@forestresearch.gov.uk)
Willoughby, I.H. and Peace, S. (2019). Delivering Resilient Forests: A summary of research. Quarterly Journal of Forestry, 113 (3), 178 – 183.
Willoughby, I.H., Tubby, K.V., Saunders, C. and Peace, S. (2019). Exploring the use of Ecoplugs for woody weed control. Quarterly Journal of Forestry, 113 (2), 96 – 101.
Willoughby, I. H., Forster, J. and Stokes, V. J. (2018). Gaultheria shallon can be controlled by the herbicides picloram, triclopyr or glyphosate if they are applied at the correct time of year. New Forests 49 (6), 757-774.
Willoughby, I.H., Harmer, R. and Forster, J. (2018). Ten conifer species with the potential for wider use in British forestry show some tolerance to six commonly used pesticides. Quarterly Journal of Forestry 112 (2), 84-91.
Willoughby, I. H. and Peace S. (2018). Reversing the spread: how can we prevent Gaultheria becoming the next Rhododendron? Quarterly Journal of Forestry 112 (3), 199-202. Reversing the spread
Tubby, K.V., Willoughby, I.H. and Forster, J. (2017). The efficacy of chemical thinning treatments on Pinus sylvestris and Larix kaempferi and subsequent incidence and potential impact of Heterobasidion annosum infection in standing trees. Forestry 90 (5), 728 – 736.
Willoughby, I.H., Stokes, V.J. and Connolly, T. (2017). Using Ecoplugs containing glyphosate can be an effective method of killing standing trees. Forestry 90 (5), 719-727.
Willoughby, I. H., Stokes, V. J. and Edwards, C. (2017). Ecoplugs containing glyphosate can be effective in preventing regrowth from Rhododendron ponticum stumps. Scottish Forestry 71 (3), 33-39.
Willoughby, I.H. and Stokes, V.J. (2015). Mixture B New Formulation adjuvant increases the rainfastness and hence effectiveness of glyphosate for rhododendron control. Forestry, 88 (2), 172-179.
Willoughby, I.H., Seier, M.K., Stokes, V.J., Thomas, S.E., Varia, S. (2015). Synthetic herbicides were more effective than a bioherbicide based on Chondrostereum purpureum in reducing resprouting of Rhododendron ponticum, a host of Phytophthora ramorum in the UK. Forestry 88 (3), 336-344.
Stokes, V.J. and Willoughby, I.H. (2014). Early weed control can increase long-term growth, yield and carbon sequestration of Sitka spruce stands in Britain. Forestry 87, 425-435.
Willoughby, I.H., Ralph Harmer, R., Morgan, G.W., Peace, A. (2013). Triclopyr applied in the winter dormant season can give effective control of bramble (Rubus fruticosus L. agg.) without damaging young tree seedlings or other non-target vegetation Forestry(86): 59-69. (PDF-1520K)
Willoughby, I.H., Jinks, R.L., Morgan, G.W., Pepper, H., Budd, J. and Mayle, B. (2011). The use of repellents to reduce predation of tree seed by wood mice (Apodemus sylvaticus L.) and grey squirrels (Sciurus carolinensis Gmelin). European Journal of Forest Research, 130, 601-611.
Stokes, V. and Willoughby, I. (2011). The impact of bracken control on establishment of Corsican pine (Pinus nigra subsp. laricio (Maire)) and on pine weevil (Hylobius abietis (L.)) damage. Aspects of Applied Biology 108, 217-224.
Stokes, V. and Willoughby, I. (2011). A comparison of Cover crops, direct seeding and herbicides in the establishment of ash trees (Fraxinus excelsior (L.)) in lowland Britain. Quarterly Journal of Forestry 105 (1), 19-28. FR_Stokes_V_and_Willoughby_I_QJF_Cover_crop_direct_seeding_herbicides_2011.pdf(1017 KB)
McCarthy, N., Bentsen, N.S., Willoughby, I. and Balandier, P. (2011). The state of forest vegetation management in Europe in the 21st century. European Journal of Forest Research 130, 7-16.
Willoughby, I. and Jinks, R.L. (2009). The effect of duration of vegetation management on broadleaved woodland creation by direct seeding. Forestry 82 (3), 343-359.
Willoughby, I., Stokes, V. and Kerr, G. (2009). Side shelter on lowland sites can benefit early growth of ash (Fraxinus excelsior L.) and sycamore (Acer pseudoplatanus L.). Forestry 82 (2), 199-210.
Willoughby, I. and Jinks, R.L. (2009). The effect of duration of vegetation management on broadleaved woodland creation by direct seeding. Forestry 82 (3), 343-359.
Willoughby, I., Stokes, V., Poole, J., White, J.E.J. and Hodge, S.J. (2007). The potential of 44 native and non-native species for woodland creation on a range of contrasting sites in lowland Britain (PDF-1311K). Forestry, 80 (5), 531-553.
Willoughby, I., Dixon, F.L., Clay, D.V. and Jinks, R.L. (2007). Tolerance of broadleaved tree and shrub seedlings to preemergence herbicides (PDF-924K). New Forests 34, 1-12.
Harmer, R. and Willoughby, I. (2007). Controlling bramble within an oak woodland using herbicides. Aspects of Applied Biology 82, 165-173.
Stokes, V.J. and Willoughby, I. (2007). Tolerance of trees to foliar acting herbicides. Aspects of Applied Biology 82, 91-101.
Willoughby, I., Clay, D.V. and Dixon, F.L. (2006). Willoughby, I. Clay, D. V., Dixon, F. L. and Morgan, G. W. (2006). The effect from different weed species on the growth of Betula pendula seedlings. Canadian Journal of Forest Research 36 (8), 1891-1899. (A full PDF of this publication is available here.)
Willoughby, I., Dixon, F.L. and Clay, D.V. (2006). Dormant season vegetation management in broadleaved transplants and direct sown ash (Fraxinus excelsior L.) seedlings. Forest Ecology and Management 222, 418-426.
Willoughby, I., Jinks, R.L. and Stokes, V. (2006). The tolerance of newly emerged broadleaved tree seedlings to the herbicides clopyralid, cycloxydim and metazachlor (PDF-824K). Forestry 79 (4): 599-608.
Dixon, F.L., Clay, D.V., and Willoughby, I. (2006). The efficacy of pre-emergence herbicides on problem weeds in woodland regeneration (PDF-22K). Crop Protection 25 (3), 259-268.
Clay, D.V., Dixon, F.L. and Willoughby, I. (2006). Weed control in mist-propagated Sitka spruce (Picea sitchensis (Bong. Carr.) cuttings. Quarterly Journal of Forestry, 100 (3) 193-200. (A full PDF of this publication is available here.) (PDF-905K)
Dixon, F.L., Clay, D.V. and Willoughby, I. (2006). Evaluation of the selectivity of herbicides as potential replacements for atrazine in forestry (PDF-5587K). Scottish Forestry 60 (3), 6-14.
Dixon, F.L., Clay, D.V., and Willoughby, I. (2006). The potential of safeners and protectants to increase tolerance of tree seeds to pre-emergence herbicides (PDF-505K). Quarterly Journal of Forestry 100 (2) 107-114.
Dixon, F.L., Clay, D.V., and Willoughby, I. (2006). The efficacy of graminicides on grass weed species of forestry (PDF-20K). Crop Protection, 2006 Vol 25 (9), pages 1039-1050.
Jinks, R.L., Willoughby, I. and Baker, C. (2006). Direct seeding of ash (Fraxinus excelsior L.) and sycamore (Acer pseudoplatanus L.): the effects of sowing date, site conditions, and pre-emergent herbicides on seedling emergence and survival. Forest Ecology and Management 237, 373-386.
Little, K., Willoughby, I., Wagner, R.G., Adams, P., Frochot, H., Gava, J., Gous, S., Lautenschlager, R.A., Örlander, G., Sankaran, K.V. and Wei, R.P. (2006). Towards reduced herbicide use in forest vegetation management. Southern African Forestry Journal 207, 63-79. Towards reduced herbicide use in forest vegetation management (PDF-279K)
Clay, D.V., Dixon, F.L. and Willoughby, I. (2005). Natural products as herbicides for tree establishment (PDF-92K). Forestry 78 (1), 1-9.
Summary and practical implications
Dixon, F.L., Clay, D.V. and Willoughby, I. (2005). An investigation into the relative efficacy of herbicides for the control of Deschampsia flexuosa (L.) Trin. in woodland establishment. Forestry 78 (3), 229-238. (A full PDF of this publication is available here.) (PDF-106K)
Dixon, F.L., Clay, D.V. and Willoughby, I. (2005). Tolerance of young trees to applications of clopyralid. Forestry 78 (4).
Summary and practical implications
Willoughby, I., Jinks, R.L., Kerr, G. and Gosling, P.G. (2004). Factors affecting the success of direct seeding for new woodland creation. Forestry 77 (5), 467-482.
Summary and practical implications
Thomson, A.J. and Willoughby, I. (2004). A web based expert system for advising on herbicide use in Great Britain (PDF-208K). Computers and Electronics in Agriculture 42 43-49.
Summary and practical implications
Willoughby, I., Clay, D.V. and Dixon, F.L. (2003). The effect of pre-emergent herbicides on germination and early growth of broadleaved species used for direct seeding (PDF-81K). Forestry 76 (1), 83-94.
Brown, A., Willoughby, I., Clay, D.V., Moore, R and Dixon, F.L. (2003). The use of dye markers as a method of reducing herbicide use and potential environmental impacts (PDF-354K). Forestry 76 (4) 371-384.
Dixon, F.L., Clay, D.V., and Willoughby, I. (2002). Susceptibility of woodland plants to herbicide drift (PDF-356K). Quarterly Journal of Forestry 96 (1), 32-36.
Dixon, F.L., Clay, D.V. and Willoughby, I. (2000). Aspects of Applied Biology 58. Vegetation management in changing landscapes. Association of Applied Biologists, Horticulture Research International, Wellesbourne, Warwick. (Download a full PDF (1444 KB) of this publication).
Harmer, R., Willoughby, I. and Robertson, M. (2000). Aspects of Applied Biology 58. Vegetation management in changing landscapes. Association of Applied Biologists, Horticulture Research International, Wellesbourne, Warwick. (A full PDF (1510 KB) of this publication is available here.)
Willoughby, I. (1999). The control of coppice regrowth in roadside woodlands (PDF-167 KB). Forestry 72 (4), 305-312.
Willoughby, I (1999). Vegetation management in farm forestry – a comparison of alternative methods of inter-row management (PDF-183K). Forestry 72 (2), 109-121.
Willoughby, I. (1999). Future alternatives to the use of herbicides in British forestry (PDF-83K). Canadian Journal of Forest Research 29 (7), 866-874.
Willoughby, I. (1997). Glyphosate rain fastness(622 KB) Quarterly Journal of Forestry 91 (3), 203-210.
Willoughby, I. (1996). Dormant season application of broad spectrum herbicides in forestry (PDF-1820K). Aspects of Applied Biology 44, Vegetation management in forestry, amenity and conservation areas : Managing for multiple objectives. Association of Applied Biologists, Horticulture Research International, Wellesbourne, Warwick, 55-62.
Löf, M., Ersson, B.T., Hjältén, J., Nordfjell T., Oliet, J.A. and Willoughby, I. (2015). Chapter 5: Site Preparation Techniques for Forest Restoration. In Stanturf, J.A. (Ed.) (2015). Restoration of Boreal and Temperate Forests, Second Edition. CRC Press. www.crcpress.com ISBN: 978-1-4822-1196-2, eBook ISBN: 978-1-4822-1197-9
Willoughby, I., Wilcken, C., Ivey, P., O’Grady, K., and Katto, F. (2009). Forest Stewardship Council guide to integrated pest, disease and weed management in FSC certified forests and plantations (PDF-1290K). FSC Technical Series No. 2009-001.
Willoughby, I., Balandier, P., Bentsen, N.S., McCarthy, N. and Claridge, J. (Eds.) (2009). Forest vegetation management in Europe: current practice and future requirements. COST Office, Brussels. 156 pages.
Carter, A.D. and Willoughby, I. (2005). Farm woodland management, 40pp. In, Soffe, R.J. (ed.) (2005) The Countryside Notebook. Blackwell Science, Oxford.
Willoughby, I., Clay, D.V. and Moore, R. (2002). The identification of dye markers to improve targeting and help achieve reductions in herbicide use. In, Frochet, H., Collet, C., Balandier, P. (comp.) (2002) Fourth international conference on forest vegetation management : popular summaries. Institut National de la Recherché Agronomique 54 280 Champenoux, France, 230-232.
Thomson, A.J. and Willoughby, I. (2002). A web-based expert system for advising on herbicide use in Great Britain. In, Frochet, H., Collet, C., Balandier, P. (comp.) (2002) Fourth international conference on forest vegetation management : popular summaries. Institut National de la Recherché Agronomique 54 280 Champenoux, France, 237-239.
Clay, D.V., Dixon, F.L. and Willoughby, I. (2002). Natural product herbicides for tree establishment. In, Frochet, H., Collet, C., Balandier, P. (comp.) (2002) Fourth international conference on forest vegetation management : popular summaries. Institut National de la Recherché Agronomique 54 280 Champenoux, France, 24-26.
Willoughby, I., Moore, R. and Nisbet, T. (2022). The integrated management of Hylobius abietis in UK forestry. Forest Research Research Note, 34pp.
Willoughby, I. (2013). Using chemicals in the forest. Operational Guidance Booklet 15. Forestry Commission internal report. Forestry Commission, Edinburgh. 73 pp.
Willoughby, I. (2007). Using dye markers to reduce pesticide use (PDF-610K). Forestry Commission Technical Note 16. Forestry Commission, Edinburgh.
Willoughby, I., Harrison, A., Jinks, R.L., Gosling, P.G., Harmer, R. and Kerr, G. (2007). The potential for direct seeding of birch on restock sites (PDF-386K). Forestry Commission Information Note 84. Forestry Commission, Edinburgh.
Willoughby, I., Jinks, R.L., Gosling, P.G., and Kerr, G. (2004). Creating new broadleaved woodlands by direct seeding (PDF-647 KB). Forestry Commission Practice Guide, 50 pages.
Willoughby, I., Evans, H., Gibbs, J., Pepper, H., Gregory, S., Dewar, J., Pratt, J., McKay, H. (2004). Reducing pesticide use in forestry. Forestry Commission Practice Guide, Forestry Commission, Edinburgh, 140 pages.
Willoughby, I and Clay, D. (1999). Herbicide update. Forestry Commission Technical Paper 28. Forestry Commission, Edinburgh, 49 pages.
Willoughby, I and Palmer, C. (1997). Weed control in Christmas tree plantations (PDF-2287K). Forestry Commission Field Book 15. Stationary Office, London, 41 pages.
Willoughby, I. (1996). Noxious weeds (PDF-2718 KB). Forestry Commission Research Information Note 274. Forestry Commission, Edinburgh, 8 pages.
Willoughby, I. (1996). Herbicide update (PDF-1859 KB). Forestry Commission Research Information Note 279. Forestry Commission, Edinburgh, 12 pages.
Willoughby, I. and Clay, D. (1996). Herbicides for farm woodlands and short rotation coppice. Forestry Commission Field Book 14. HMSO, London, 60 pages. Main sections (PDF-3843 KB), Appendices (PDF-3175 KB). Please note that these PDF files form an integral whole, and should always be downloaded and read in conjunction with each other.
Willoughby, I., Kerr, G., Jinks, R. and Gosling, P. (1996). Establishing new woodlands by direct sowing (PDF-1420 KB). Forestry Commission Research Information Note 285. Forestry Commission, Edinburgh, 8 pages.
Willoughby, I. (1996). Weed control when establishing new woodlands by direct sowing (PDF-1133 KB). Forestry Commission Research Information Note 286. Forestry Commission, Edinburgh, 8pp.
Willoughby, I. and Moffat, A. (1996). Cultivation of lowland sites for new woodland establishment (PDF-2346 KB). Forestry Commission Research Information Note 288. Forestry Commission, Edinburgh, 8 pages.
Willoughby, I (1995). Farm woodlands research. Forestry Commission Research Division Leaflet. Forestry Commission Research Division, Alice Holt Lodge, Farnham, Surrey, 2 pages.
Willoughby, I. and Dewar, J. (1995). The use of herbicides in the forest. Forestry Commission Field Book 8. HMSO, London, 318 pages.
McCavish, W.J. and Insley, I. (1992) (revised by Willoughby, I. (1995)). Herbicides for sward control among amenity trees (PDF-364 KB) Arboriculture Research Note 27/95. Arboriculture Advisory and Information Service, Alice Holt Lodge, Farnham, Surrey, 5 pages.
Willoughby, I. (2024). Can non-hazardous spray adjuvants help in the battle to remove Rhododendron ponticum from our woodlands? Scottish Forestry 78 (1), 40-43. rsfs.org.uk
Willoughby, I., Nisbet, T. and Thomas, H. (2023). Can acetamiprid be safely used to protect young trees from Hylobius damage? Forestry and Timber News 115, 54-55. confor.org.uk/news/ftn-magazine
Willoughby, I., Moore, R. and Nisbet, T.R. (2022). The integrated management of Hylobius abietis in UK forestry. Forestry and Timber News 110, 66. confor.org.uk/news/ftn-magazine
Willoughby, I.H. (2021). Alternatives to using glyphosate and propyzamide for grass weed control in forests. Forestry and Timber News 108, 60-61. confor.org.uk/news/ftn-magazine
Willoughby, I.H. and Moore, R. (2021). Defending our trees. What’s the latest in the battle against Hylobius? Trees, summer 2021, 20-21. www.charteredforesters.org
Willoughby, I.H. and Moore, R. (2020). Hylobius attack: other ways of protection. Forestry and Timber News 102, 64-65. (for a PDF copy of this article please contact ian.willoughby@forestresearch.gov.uk)
Willoughby, I. (2019). Direct seeding – a viable technique for the restoration of upland native woodland. Forestry and Timber News, October 2019, 67-69.
Willoughby, I. (2004). Using colour to protect woodlands (PDF-529 KB). The Colourist, Issue 1, Spring, p6.
Willoughby, I. (2004). Reducing pesticide use in forestry (PDF-414 KB). Forestry and British Timber, 33 (2).
Willoughby, I. (2004). Expert help on herbicide selection (PDF-375 KB). Forestry and British Timber, 33 (2).
Willoughby, I., and Clay, D.V. (2002). Natural product herbicides in forestry: what are the prospects? (PDF-756 KB). Forestry and British Timber 31 (2), 22-25.
Willoughby, I. (2001). Seeing Red (or Blue) – benefits of dye markers in spraying applications (PDF-1000 KB). Forestry and British Timber 30 (2), 22-24.
Willoughby, I. and Claridge, J. (2000). Trees and weeds, an update on herbicides (PDF-628 KB). Forestry and British Timber 29 (2), 30-31.
Willoughby, I. (1999). Herbicides in forestry – how are they approved and used? (PDF-1121 KB) Forestry and British Timber, 28 (2), 27-30.
Willoughby, I. (1997). Using additives with forestry herbicides (PDF-898 KB). Forestry and British Timber 26 (2), 41-43
Willoughby, I. (1997). Weeding young trees – avoiding trouble (PDF-1091 KB). Farming and Conservation 3 (3), 27-30.
Willoughby, I. (1995). Herbicides in forests and farm woodlands (PDF-454 KB). Forestry and British Timber 24 (2), 23 – 25.
Willoughby, I. (1995). Revised long term off – label arrangements for pesticides (PDF-303 KB). Forestry and British Timber 25 (3), 21 – 22.