The timing of leafing for native trees in Ireland can vary depending on these factors:
Temperature: Temperature is a crucial factor that affects when trees begin to leaf out. As the weather becomes warmer in spring, the buds on the trees start to swell and open, leading to the emergence of new leaves.
Day length: Day length or photoperiod is another crucial factor that influences the timing of leafing in trees. As the days start to get longer in spring, the trees receive more sunlight, which triggers the production of hormones that stimulate growth and leafing.
Moisture: Moisture is another important factor that affects when trees leaf out. Trees need sufficient moisture to grow and produce new leaves, and a lack of water can delay the leafing process.
Soil nutrients: Soil nutrients are essential for tree growth and health. Trees require sufficient nutrients, such as nitrogen and phosphorus, to produce healthy leaves.
Genetics: The genetics of the tree species also play a significant role in determining when the tree will leaf out. Different tree species have evolved to leaf out at different times of the year, depending on their natural habitats and environmental conditions.
It's important to note that the leafing times can vary depending on the location in Ireland and the prevailing weather conditions. For example, a warm spring may lead to earlier leafing times, while a cooler spring may result in delayed leafing.
Generally native trees in Ireland come into leaf from mid February to mid May
General month by month guide with reasons for variables list above.
February
Blackthorn Prunus Spinosa
March
Hawthorn Crataegus monogyna
Elder Sambucus nigra
Hazel Corylus avellana
Willow Salix caprea
April
Birch Downy Betula pubescens
Birch Silver Betula pendula
Bird Cherry Prunus padus
Rowan Sorbus aucuparia
Spindle Euonymus europaeus
Oak Pedunculate Quercus robur
Oak Sessile Quercus petraea
Alder Alnus glutinosa
Crap Apple Malus sylvestris
Aspen Populus tremula
May
Ash Fraxinus excelsior
Aside from these deciduous trees there are a number of evergreens in ireland that do do lose their leaves
Scots Pine Pinus sylvestris
A coniferous tree with a distinctive red-brown bark and long needles that can grow up to 35 meters tall.
Holly Ilex aquifolium
A small evergreen tree or shrub with shiny green leaves that are spiny at the edges, and produces red berries in the winter.
Yew Taxus baccata
A slow-growing coniferous tree that can live for thousands of years, with dark green needles and red berries that are toxic to humans.
Juniper Juniperus communis
A low-growing evergreen shrub or tree with blue-green needle-like leaves and small blue-black berries.