Tree terms: l
- la niña
- ladders
- lady’s slipper
- lagoon
- lammas growth
- lamp black
- land drain
- Land Drainage Act 1991
- Land registry
- land survey
- Land Trust (Land Restoration Trust)
- landfill
- landrace
- Lands chamber
- Lands tribunal
- landscape
- landscape architecture
- landscape character
- landscape character assessment (LCA)
- landscape character network
- landscape design
- landscape garden style
- Landscape Institute (LI)
- landslip
- LANTRA
- lap panel fence
- lapsed coppice
- lapsed pollard
- larch lap fence
- large blue butterfly
- late wood
- late-mature
- lateral displacement survey
- lateral drain
- lateral shoot
- latex
- lawn
- lawsuit
- Lawton report
- layer
- laying course
- leaching
- leader
- leading shoot
- leaf
- leaf analysis
- leaf angle index
- leaf area index
- leaf guard
- leaf litter
- leaf miner
- leaf mould
- leaf scorch
- leaf temperature
- leaking drain
- lean
- legal title
- lenticel
- Lepidoptera
- leptospirosis (Leptospira spp.)
- lesion
- lesser knotweed (Persicaria campanulata)
- lesser whirlpool ram’s-horn snail
- level 3 Certificate in arboriculture (technician’s certificate)
- level survey (brick course)
- level survey (floor)
- lever arm
- ley
- Leyland cypress (×Cupressocyparis leylandii)
- LI
- liability
- lichen
- life cycle analysis
- Lifting Operations and Lifting Equipment Regulations 1998
- light tube
- light-demanding
- lighting
- lightning damage
- ligneous
- lignicolous
- lignin
- limb
- lime
- lime mortar
- lime stabilization
- lime-induced chlorosis
- limits to growth
- line thinning
- linear drain
- lintel
- lion-tailing
- liquid limit
- liquidity index
- listed building consent
- listing
- lithology
- litigation
- litter
- little ice age
- liverworts
- living hoarding
- LNP
- LNR
- load
- load-bearing capacity
- loam
- Local area agreement
- local authority
- Local development framework
- local development order
- local government
- Local Government (Miscellaneous Provisions) Act 1976
- Local Government Act 2000
- local green space
- local nature partnership
- local nature reserve (LNR)
- local plan
- Local planning authority
- local site
- Local strategic partnership
- Local Wildlife Trust
- Localism Act 2011
- locally listed
- log
- log (firewood)
- LOLER
- London plane
- London tree and woodland grant scheme
- London Tree Officers’ Association
- Lonsdale column
- lop and top
- lopping
- Lorette system
- loss adjuster
- low input
- lower plant
- low-intensity managed woodland
- lowland
- LPA
- LTOA
- lumen
- Lyme disease (Borrelia spp.)
- lynchet