Planting
When and how to plant
Most tree and shrub seedlings will spend their first year in the seedbed – more if germination is delayed or growth very variable or slow.
After replanting in the transplant bed, where they have more space, the trees may be left for a further one or two seasons, depending on growth and size, which is usually related to the type of tree i.e. the species.
Some species transplant easily – others, such as gorse, holly and blackthorn do not transplant well and are best sown on site or moved to their final site as very small seedlings. Moving young trees is always stressful for them -the faster it can be done the better, without damaging the tiny root hairs or allowing them to dry out.
The normal planting season extends from October till the end of March. Do not transplant in heavy frost. and take extra care in cool, drying east winds.
Transplanting is stressful for all young plants. They should be replanted in prepared soil, then well firmed in at the same level as they were before i.e. the same position between roots and trunk – there will be a colour change to guide you. Dig a good sized hole and spread the roots out, not leaving them squashed or twisted.
If your young trees have been grown in pots or containers, they may be left until they are older and planted out keeping the complete mass of roots and soil together. Do not leave them in pots too long, or the roots become cramped and there is real growth check before the roots spread out in their new site, which allows growth to begin again.
We tend to think of roots as big strong parts of the tree which anchor it to the ,round. but as with other plants. it is the fine delicate root tips and root hairs which do the main job of absorbing water and nutrients – if they are damaged or cut, the tree cannot grow as well. (When root pruning only the longest roots are cut. leaving the side roots to form a healthy mass of new rootlets which increases this absorbtive area).
If the trees are left for four years or more in their nursery beds. they get beyond the stage of easy transplanting and the chances of moving them successfully decrease sharply. Some species are more tolerant than others.
Birch should be moved young, oak and rowan seem to be able to survive later moves.
The same principles apply to cuttings, which should be moved carefully taking soil with the roots if possible.
Willows are often planted on the final site, directly into wet ground, which means they do not have to be moved at all – the easiest way!
Always water young trees and cuttings soon after re¬planting.
Where to plant your trees
You may be growing trees from seed with a clear idea of where you want to plant them. In many ways this is ideal, as you can choose the species most suitable for the site you have in mind. You may be growing trees in order to supply other people, schools, community groups, or local nature reserves, in which case local provenance has a particular value.
Always check that the area you have in mind is not important for conservation as it is, in which case trees might actually detract from the wildlife value. Peatland and bogs should mainly be left unplanted.
We have tried to suggest which species are more suitable for small spaces or gardens, where you will only need a few trees or even one specimen tree. Even if you only want one to last, it is worth planting several and then selecting out the best while transplanting the rest.
You need to plan for how long a tree will last and how much it will grow – do not plant close to walls, buildings or historic monuments, as all these may be damaged by tree roots. Always over estimate the space trees will need above ground and below, because roots spread beyond the canopy in order to collect rain dripping off leaves all around the tree. Once planted, tree roots should not be disturbed.
Care of young trees
Young trees do best if they are given a good start. After all your care in collecting seed and rearing young trees, it is all too easy to lose them once the time comes to plant them out in their final site. To avoid this disheartening outcome, spend some time on site preparation just as you did for the seeds and keep an eye on the young trees.
Good soil can be improved by cultivation, thorough digging and mixing in compost or farmyard manure if available. Thick grass and weeds should be cleared from the planting site, either by cultivation or use of herbicide, which if it is long-lasting will also prevent re-growth around the young tree.
Planting into good soil, already cleared of other vegetation, is ideal. If trees are to be planted in sub soil or rubble, provide them with good top soil in a pit around the roots to get them started.
If you have to plant into dense grassland, clear or kill a small area before you put the trees in place.
Use of a mulch- dark plastic or organic matter such as wood chips – around the trunk will keep the ground clear of competing vegetation and help conserve moisture.
Even in Ireland, many young trees die from lack of moisture. Water young trees at planting and keep on watering during the first summer in dry weather.
Grass and other small plants compete for water and nutrients.The worst thing you can do is to cut grass around young trees as this will encourage the grass to re-grow and take even more from the soil. Never use strimmers near trees – they are most effective at ‘ring barking’ small trees so killing them.
So long as growth of grass and other plants is not too vigorous, trees should outgrow the competition.
But remember to clear around trunks while they are getting started, to allow the trees to grow straight and true. If you care for your trees in the early stages, they will repay you by growing well.
Trees do not generally need fertiliser – after all, they are natural vegetation and should be able to grow naturally. If you do think it is needed, low nitrogen types like potato fertiliser are best.
They do need the soil to suit them: alder and willow can tolerate very wet conditions, birch grows on acid soils, shrubs such as spindle, guelder rose and buckthorn seem to prefer limestone soils, rowan and gorse need well drained ground.
Always consider the ‘appropriateness of place’ when considering what trees to plant where. Seek advice if you are unsure.
Planning your woodland
If you are fortunate to have enough ground to plant a number of trees, for conservation reasons you should aim to create a woodland as close as possible to natural woods in your area. Take a look around, and see what grows there naturally. You have probably done this to begin with, in order to identify trees from which to collect seed.
Some woods consist of very few tree species. Birch woods on acid soils, ash woods on limestone, are examples of woods which are almost single species. If you are planting a difficult site, very wet, or with acid soil, your choice of trees will be restricted.
However, on better soils you have more choice. Aim for a mixture of trees to give final height such as oak and ash. with shrub species for variety – hazel, hawthorn, etc. Allow plenty of space between trees and shrubs, because shrubs cannot thrive in heavy shade.
If there are any trees and shrubs present on the site to begin with, try to keep these and incorporate them in the new planting. They may provide shelter for your new young trees.
If you have poor spindly trees on site, for example ash or hawthorn, these can always be coppiced – cut back to the stump and allowed to re-grow.
This will give young bushy growth and re-juvenates the trees.
Ideally, a wood should have trees, shrubs, and flowering plants below. If you are planting next to an existing wood, the woodland plant species will naturally colonise.
Areas under trees are increasingly shaded as the trees grow,so that meadow grasses and plants are shaded out and only early flowering or shade tolerant woodland species will be able to thrive.
You can speed this process by transferring a few spadefulls of woodland soil in winter time complete with roots and bulbs. Or ask permission to take some plants from another existing wood on similar soil: bluebells, wood sorrel, wood anemone, lesser celandine etc.
If you apply for planting grants limits may be set on the planting distance stance between trees. Planting young trees close together encourages better growth rates and straight trunks, but it does mean thinning in 15 – 20 years time. However, it is possible to plant in several groups, leaving open land between if you can afford the space, or to leave generous open glades or rides within a single planted area.
If you leave more space between trees you will have to do more weeding to ensure good growth, but it will reduce the necessity to thin out your planting in future years – people dislike destroying trees they have grown and planted, but the timber may be useful for firewood, fencing, etc.
The purpose of open glades is not only to allow extra room for tree growth, but also to encourage plants that need the extra light. These attract insects, birds, and mammals.
Research has shown that it is the woodland edge which is most used by birds rather than the centre of thick woodland.
If you walk along forest paths you will often see traces of badgers and foxes, although their setts or earths may be hidden within the wood.
Tree Shelters and Pests
Tree shelters are made from various materials in a variety of forms, square or rounded: some are manufactured locally. Shelters are used as protection against wind and weather, as a marker to remind you about small trees, and to deter rabbits, a common cause of destruction. Shelters are very worthwhile for a few young trees. Oak seems to benefit particularly, but some species do not thrive in shelters -birch, beech and pine.
If you are planting a larger area, it is worth erecting rabbit proof fencing around the perimeter rather than buying lots of tree shelters. Hares may also be a problem, and they require 15 cm shelters rather than the usual 10 cm to protect the trees.
If you have deer locally, you may have real difficulty in establishing trees. One way is to plant one of their favourites, such as willow, in a dense band all around the outside of the planted area -this is a ‘sacrifice crop’ which should protect your final woodland in the centre. Deer are not generally a problem in gardens here, but they do restrict regeneration of woodland where they are present, and will feed some distance from their home forest or estates.
Grey squirrels may be a problem in some areas of Fermanagh and Armagh, and are very difficult to exclude!
Insect pests have to be watched for in nursery situations, but once your trees are planted out as woodland, natural control and a balance of pests/predators should become established.
Record Keeping
Do keep records of all that you do – when and where you collect the seeds, how you treat them, how well they germinate and grow. The records will prove valuable to you in accumulating knowledge and may provide useful guidance for other people.
Perhaps because our woodland tradition in Ireland is not strong, we have lost some of the older skill in rearing trees. This guide reflects the experience of several groups and individuals, but we all have a lot more to learn – you can make a real contribution