Spotlight on Black Locust: A Mixed Picture Across the UK

Black Locust (Robinia pseudoacacia ‘Turbo’) continues to show contrasting performance across the Demonstrator Hubs in June. While some sites report vigorous growth and healthy foliage, others are dealing with nutrient stress, wildlife damage, or signs of tip necrosis.

Aberystwyth
No signs of pest or disease were reported. Herbicide has been applied at the base of the trees to reduce grass and weed competition.

Hillsborough
Black Locust is in full leaf, and the leaves look less chlorotic than before. Height is starting to be gained.

Chesham
Black Locust is in full leaf and one tree is in flower.

Cockle Park Farm
The trees are small with quite yellow leaves, and hare damage has been reported.

Headley Hall
Black Locust plants are looking good and bushy, with bold green leaves and good new growth. The plot is now so dense that it was difficult to access the middle.

North Wyke
No specific Black Locust update was included for this site in the June report. The next visit is planned for mid July.

Auchincruive
Trees are described simply as “huge.” Spot spraying is planned (where possible) during the first week of July.

Boghall
Trees appear bushy and healthy, although some have necrosis at the branch tips. Interrow mowing was carried out in May, with additional mowing and spot spraying planned in early July.

Black Locust remains an intriguing but variable performer. Its success appears closely tied to site conditions and wildlife pressure. While most hubs report healthy trees, a few have flagged yellowing leaves, hare damage, or tip necrosis — all factors to watch as summer progresses.

Spotlight on Eucalyptus: Beetle Infestation Raises Alarms at Chesham

Eucalyptus has faced serious challenges this month — most notably at Chesham, where the presence of the Tasmanian Eucalyptus Beetle has been confirmed. While other sites report minor maintenance or growth updates, this pest issue has prompted concern and swift action, marking a significant event in this season’s monitoring.

Chesham
Several inspections were carried out in June following the suspected presence of Tasmanian Eucalyptus Beetle larvae on E. gunnii. Damage was evident, especially on the younger regrowth of trees cut back a couple of years ago. By mid-month, larvae and beetles were confirmed, and the outbreak was widespread across both ends of the 10-year-old Eucalyptus plot.
• APHA was notified and visited the site on June 26th to collect samples for diagnosis.
• A Plant Health Form was submitted, and plant passport documentation was provided to authorities.
• The site team noted that such damage has never occurred in previous years and is being closely monitored.

Aberystwyth
Strong winds caused some damage to new growth. Aphids are present on the tips of new shoots, but no disease symptoms have been reported. Herbicide was applied around the base of the trees to suppress weeds.

Cockle Park Farm
The Eucalyptus is growing well, with no hare or pest damage observed. New growth is appearing and development is progressing normally,

Headley Hall
Some trees are bending over again, but the soil is currently too dry to allow for staking. Eggs of unknown insects were seen on some leaves. Leaf discolouration has also been noted on E. uringera, and photos have been shared for assessment.

Auchincruive
Interrow mowing and spraying are scheduled for the beginning of July. The team also requested advice on the use of tree straps, as some trees appear delicate and at risk of damage during support work.

Boghall
The Eucalyptus is looking, big, green and healthy. Similar advice is sought on tree supports.

Hillsborough
The Eucalyptus trees are growing very well. E. nitens and E. dalrympleana seem to be growing the best, with E. nitens now roughly 2 m tall. Aphids are still present.

North Wyke
No Eucalyptus update was reported. The next visit is planned for mid July.

Eucalyptus is showing its resilience across most hubs, but the situation at Chesham is being treated with particular seriousness. With APHA involved and long-term monitoring now in place, this represents the first major pest outbreak for Eucalyptus in the project’s history — and potentially an important test of biosecurity protocols.

Spotlight on Poplar: Rapid Growth and Full Leaf Emergence Across the Hubs

Poplar is growing well now that summer is here with no major issues reported at any of the sites. It remains a dependable tree at all demonstrator hubs. There are a couple of minor issues that aren’t affecting the health of the plants at some sites and these will continue to be monitored

Chesham
The SRF and SRC poplar is growing steadily, but there has been some leaf loss due to the lack of rain in June, and something is eating the leaves.

Aberystwyth
All is looking good in the poplar plots at Aberystwyth this June.

Cockle Park Farm
All is looking good in the SRC and SRF poplar plots at Cockle Park Farm with no issues or concerns reported. The Italian poplar plot has been pruned at knee height.

Headley Hall
Some leaves have been reported to have holes in them in the SRF poplar, and the SRC poplar may be following suit, but there isn’t significant damage. The trees are still growing well and putting on some good trunk growth and height.

Auchincruive
The SRF poplar here is ‘massive’, and the SRC poplar is also growing well. Pruning of the Italian polar was completed on June 23rd-25th, and slugs have been noted as a potential problem. What looks like juvenile giant willow aphids have also been seen. Spraying is planned for early July.

Boghall
The poplar is growing well both in the SRC plot and the SRF plot, with no signs of any issues. Inter-row mowing and spraying is scheduled for the first week of July.

Hillsborough
The poplar trees in both the SRC and SRF plots are putting on growth and looking healthy. Some leaves have a bubble/bulge with signs of rust, which may be a gall, but it isn’t have any significant effect on the growth or health of the plant.

North Wyke
No poplar update was reported. The next visit is planned for mid-July.

Spotlight on Miscanthus: Strong Growth with Localised Challenges
Miscanthus continues to show robust performance across the UK Demonstrator Hubs in June, with both Miscanthus giganteus and Miscanthus Athena generally thriving. Most sites report healthy growth and good canopy closure, though some are dealing with weed pressure or patchy establishment.

Aberystwyth
Both Miscanthus giganteus and Miscanthus Athena are growing well. No signs of pest or disease were reported. The canopy has closed in many areas, helping suppress weed growth. However, some gaps remain in the Miscanthus Athena plot, allowing weed grasses to persist.

Hillsborough
Both Miscanthus giganteus and Miscanthus Athena are growing back well, reaching approximately 1 metre in height. No active management was reported this month, though patches of docks, thistles, buttercups, and nettles were noted in both plots.

Chesham
Miscanthus giganteus and Miscanthus Athena were cut in March and are now outgrowing thistles. No herbicide applications are currently planned, as the Miscanthus canopy is effectively suppressing weed competition.

Cockle Park Farm
Both Miscanthus giganteus and Miscanthus Athena are growing well. Agritox herbicide was applied at 2 L/ha on 16th June. No signs of disease or hare damage were reported.

Headley Hall
Despite warm and dry conditions, both Miscanthus giganteus and Miscanthus Athena are putting on good growth. The plots are looking healthy overall.

North Wyke
The next site visit is planned for mid July.

Auchincruive
Miscanthus giganteus is growing very tall and bushy, exceeding 5 ft in height. Miscanthus Athena is also performing well, with most plants over waist height. No signs of pest or disease were reported.

Boghall
Miscanthus giganteus is getting tall and bushy, with no signs of disease or pests. Miscanthus Athena is growing well, though some bare patches remain at the bottom of the plot. Overall health is good.

Miscanthus Variety Trials

2023 Trials

Boghall: Most varieties are growing tall and looking healthy. Some inter-plot mowing and spraying are planned.
Headley Hall: Plants are growing well, but weed pressure remains. A spray of Starane (1 L/ha) was applied, though dry conditions may have reduced its effectiveness.
Aberystwyth: Canopy closure has occurred in most plots. No signs of pest or disease.
Hillsborough: Plots with good establishment are growing back well. Poorer plots are struggling. Old stems have been cleared and thistles dug out.

2024 Trials

Boghall: Most plots are struggling and appear weedy. Inter-plot mowing and spraying are planned.
Headley Hall: Plants are growing well, but weeds persist. Starane was applied, but results were limited due to dry weather. The clover cover crop is coping well.
Aberystwyth: Plants are growing well, though gaps in the canopy have allowed grass weeds to establish. Spraying is planned post-harvest.
Hillsborough: Poor establishment from last year. Some better-established plots are growing okay. Grass has been burnt off and old stems cleared.

Miscanthus remains a reliable performer across the UK, with strong growth reported at nearly all sites. Miscanthus giganteus is particularly vigorous, often achieving canopy closure and suppressing weeds. Miscanthus Athena is also performing well, though some sites report patchy establishment. The variety trials show promise, though weed pressure and dry conditions are key challenges to monitor as the season progresses.

Spotlight on Willow: Mixed Health and Wildlife Pressure Across Sites

Willow continues to show varied performance across the UK Demonstrator Hubs in June. While many plots are thriving with good canopy closure and new growth, others are facing challenges from sawfly, deer, and black spot. The variety trials also show a range of outcomes, with some plots performing well and others under pressure from pests and weeds.

Aberystwyth

The 0.5 ha Salix plot is recovering well after earlier sawfly damage, with new leaves appearing at the tips of stems. Some varieties are showing signs of black spot. Minor sawfly damage and black spot were also noted in the variety trial.

Hillsborough

Stems are thickening up nicely. However, many varieties are showing yellow-brown spots, and heavy buttercup pressure is affecting double rows in the variety trial. The 0.5 ha plot has been mown, and some varieties are showing very yellow leaves.

Chesham

The 0.5 ha Willow plot is leafing up well with young catkins visible. No signs of leaf curling or black spot were observed.

Cockle Park Farm

The 0.5 ha Willow plot shows signs of leaf damage, though no sawfly were observed. Black spot and yellowing leaves are present, and hare damage has been reported in the Willow trial.

Headley Hall

The 0.5 ha Willow plot has experienced significant leaf loss, particularly in the lower canopy. Leaves at the top show signs of being eaten, though the cause is unclear due to height. The variety trial is performing better, with only minor leaf curling and brown edges noted.

North Wyke

No specific Willow update was included for this site in the June report.

Auchincruive

Complete canopy closure has been achieved in the 0.5 ha Willow plot. Slight insect damage was noted, mainly around the plot edges. Spot spraying and strimming are planned for the concrete section.

Boghall

Canopy closure has occurred in most parts of the 0.5 ha Willow plot. Significant sawfly damage was observed at the bottom of the plot, though the tops of trees remain healthy. Fresh deer damage was also noted, and black larvae (likely Chrysomela spp.) were found. The variety trial is performing well overall, with some ghosting and midribbing noted.

Willow shows a mixed picture across the UK Demonstrator Hubs. While many plots are thriving, others are facing challenges from pests such as sawfly and deer, as well as fungal issues like black spot. The variety trials highlight the importance of site-specific conditions and pest management. Continued monitoring and targeted interventions will be key to maintaining healthy growth through the summer.

Spotlight on Sida: Rapid Growth and Promising Establishment

Sida is showing strong growth across most UK Demonstrator Hubs in June. The crop is generally healthy and vigorous, with some sites reporting plants reaching impressive heights. While a few minor issues such as yellowing leaves or weed competition were noted, overall performance is encouraging.

Aberystwyth

Sida is growing well, with no signs of pest or disease. Weeds between the rows have been cut using a bladed strimmer.

Hillsborough

Leaves are coming on strong, and the crop appears healthy. Inter-row glyphosate application was carried out on 30 June.

Chesham

Sida is growing well, with some plants reaching up to 2 metres in height. Photos are available on the UKCEH shared site.

Cockle Park Farm

Sida rows are visible but still quite small. Most plants are present, though some are yellowing.

Headley Hall

Sida is putting on good upward growth. Some lower leaves are turning yellow, though it’s unclear whether this is a natural part of development or a stress response.

North Wyke

No specific update on Sida was included in the June report.

Auchincruive

Sida is growing very quickly. Most plants have greened up and are looking healthy. A photo of the crop is included in the site’s June update.

Boghall

Rhizome-planted Sida is growing vigorously—big, green, and likely to flower soon. Plug plants are smaller but also healthy and green.

Sida is performing well across the UK Demonstrator Hubs, with strong growth and healthy foliage reported at most sites. While some yellowing and weed competition were noted, these issues appear minor. The crop’s rapid development and resilience make it a promising option for biomass production, and continued monitoring will help assess its full potential as the season progresses.

Spotlight on Reed Canary Grass: Steady Growth with Minimal Issues

Reed Canary Grass continues to perform steadily across the UK Demonstrator Hubs. While not the most dynamic crop in terms of visual growth, it remains resilient and low-maintenance. Most sites report minimal pest or disease issues, with weed management being the primary focus.

Aberystwyth

Large thistles in the plot have been removed by hand. No signs of pest or disease were reported.

Hillsborough

No change was reported this month. The crop appears stable, with no major concerns noted.

Chesham

Nothing new to report. Larger weeds have been hand-rogued or cut back.

Cockle Park Farm

Reed Canary Grass is showing very good growth. No damage from disease, hares, or deer has been observed.

Headley Hall

Growth is steady, though limited by dry conditions. Other grass trials at the site have also experienced slow development due to the weather.

North Wyke

No specific update on Reed Canary Grass was included in the June report.

Auchincruive

Missed patches were re-sprayed with glyphosate (4 L/ha via knapsack and boom) on 11 June.

Boghall

The plot was sprayed off on 6 May. No further issues were reported.

Reed Canary Grass remains a low-input, stable performer across the Demonstrator Hubs. Weed control continues to be the main management task, with most sites reporting minimal pest or disease pressure. While growth may be slower in drier regions, the crop is holding its own and contributing to the diversity of biomass options under evaluation.

Spotlight on Switchgrass: Slow Start but Steady Progress

Switchgrass is showing mixed progress across the UK Demonstrator Hubs in June. While some sites report slow emergence and weed competition, others are seeing steady growth. The crop’s performance appears closely tied to local weather conditions, particularly rainfall and temperature.

Aberystwyth

Switchgrass seedlings are beginning to emerge, but a high number of weed seedlings are also present. These could compete with the crop and may require management attention.

Hillsborough

No update was provided for Switchgrass this month.

Chesham

Nothing new to report. Larger weeds have been hand-rogued or cut back.

Cockle Park Farm

Switchgrass is growing very slowly. No signs of disease or hare damage have been observed.

Headley Hall

Growth is limited due to dry conditions. Like other grass trials at the site, Switchgrass is struggling to establish in the current weather.

North Wyke

The next site visit will take place in mid July.

Auchincruive

Missed patches were re-sprayed with glyphosate (4 L/ha via knapsack and boom) on 11 June.

Boghall

The plot was sprayed off on 6 May. No further issues were reported.

Switchgrass is progressing slowly at many sites, with dry conditions and weed competition being the main challenges. While some plots are beginning to establish, others may require re-sowing or additional weed control later in the season. Continued monitoring will be important to assess its viability under varying UK conditions.