Populus spp.

Hybrid poplars (timber)

Physical Traits & Growth

Typical max. heightiMaximum height in typical conditions, in metres. Full data also shows maximum achievable height in exceptional conditions.: Depends on variety

Max. canopy widthiLikely maximum horizontal width of the canopy, in metres: Depends on variety

Size of shadowiSize of shadow based on a fully grown tree, categorised as low, medium or high: Moderate to high, depending on variety

Canopy densityiShading intensity of the canopy when in full leaf. Categorised from open to dense.: Depends on variety

Leaf emergenceiTime of leaf emergence, categorised as very early, early, late, or evergreen: Early (Apr to Nov 1)

Growth rateiHow quickly the tree grows during establishment. Categorised as low, moderate or high, with very high used in exceptional cases.: Very high 4

LongevityiExpected lifespan of the tree: N/A, harvested on rapid rotation

Management & Systems

Typical systemsiCommon agroforestry or silvicultural systems where this species is used: Arable or pasture, lowland 1

Approach to silvicultureiCoppicing and pollarding ability: High forest 3

Establishment requirementsiCommon requirements to establish the tree: Highly intolerant of weed competition 6

Management requirementsiCommon long-term management needs such as pruning. Categorised as low, moderate or high.: Regular pruning 23

Pruning timeiOptimal season for pruning: Winter (mid) 1

Hybrid Poplars, Cirencester, UK / Paul Burgess / https://creativecommons.org/licenses/by-sa/4.0/deed.en

Products & Economy

Food productsiCommon food products such as fruits and nuts: –

Wood productsiCommon wood products, including timber, turnery, and pulp:
Timber 3
Max YC 22 24

BiomassiCommon biomass products such as fuelwood: Bioenergy 3

Speciality productsiOther speciality and niche products: –

Time until market (food)iNumber of years until the tree produces food products: –

Time until market (timber)iNumber of years until the tree produces wood products: Typically 30-40 years, exceptionally 22 years 6

Ecology & Utility

Nutrient and organic matter accumulationiRough estimate of soil-improving properties, with larger and deeper-rooting trees predicted to have higher value. Categorised as low, moderate or high.: High – moderate to deep roots and high canopy area

Nitrogen fixationiNitrogen-fixing properties, categorised as yes or no: No

High carbon sequestrationiAll trees sequester carbon, but faster-growing, larger trees generally have higher sequestration potential.:
Short-term (20 years): Very high
Medium-term (40 years): Very high
Long-term (60 years): Very high

Native status in the UKiCategorised as native, long-established, or recent introduction.: Hybrids, typically derived from non-native species

High wildlife valueiMost trees are likely to be of some value to wildlife, but some trees are of generally higher value to various wildlife groups:
Relatively low 5
Highest value for foliage invertebrates 5

Other environmental impactsiOther impacts such as water consumption and nutrient leaching:
High water consumption in wet conditions 1
High potential to reduce nutrient leaching 5

Pollinators

Flowering period (pollinator benefit)iTypical flowering months: Apr-May 1

High pollen and nectar value for pollinatorsiValue of flowers to pollinators: Low 1

Susceptibility & Risks

Risk of toxicity to livestockiReported potential toxicity to livestock, categorised as yes or no. Toxicity is complex and often context-specific.: None known

Risks to farming operationsiOther risks such as suckering roots, very large tree size, secondary host for aphids, and flammability: Some cultivars are overwintering hosts of aphids of lettuce, carrots and celery 4

Disease susceptibilityiSusceptibility of the tree (not tree products) to diseases, e.g. fungal and bacterial disease:
High, but dependent on variety
Highly susceptible to various diseases including bacterial and fungal cankers, leaf rusts, leaf spot 5
Recommended to plant a mixture of varieties to minimise insect and disease damage 5

Invertebrate pest susceptibilityiSusceptibility of the tree (not tree products) to invertebrate pests, e.g. aphids and other insects:
High, but dependent on variety
Susceptible to defoliation from sawflies and leaf beetles, and damage to timber from boring flies 5

Vertebrate damage susceptibilityiSusceptibility of the tree (not tree products) to vertebrate pests, e.g. squirrels and deer:
High
Susceptible to bark stripping by grey squirrels 5
High sensitivity to browsing 7