At the end of National Tree Week, which this year is also the weekend when many people chose and buy their Christmas tree, it seemed appropriate to answer a few of the more common questions we have from clients about the trees in the garden.
When is a Tree a Shrub?
Trees and shrubs are both woody perennials and closely related in many ways. The simple definition or difference between a tree and a shrub relates not purely to the overall height of the plant, as many people think, but to whether it is naturally a single stemmed plant or a multi stemmed plant.
A tree has one main stem or trunk. When mature, it will generally branch out at a height of over 1.5 metres having attained a trunk of at least 75 cm in diameter at that height; a tree will generally be taller than 4 metres. This botanical definition is easy to apply to fully grown trees, but perhaps less so to younger trees also known as saplings and to those which have been specially pruned.
A shrub has a multi stemmed form; that is, it has more than one main trunk from near ground level. Most shrubs grow to less than thirteen feet at maturity, although there are a few exceptions. Smaller shrubs, those less than six feet (two metres) high are often termed sub-shrubs. Shrubs are more likely than trees to have branches that grow out from the main stems at or near ground level.
There are exceptions, of course; some trees, Japanese maples for example, are naturally multi-stemmed but are still classified as a tree. And then there are the legal interpretations of the botanical description…
Why am I sweeping leaves off my lawn all year?
A frequent question when the lawn is surrounded by evergreens and conifers. Many people assume that because an evergreen tree keeps its leaves all year it doesn’t drop the leaves in autumn as deciduous trees do.
What actually happens is that evergreen trees – both conifers and broadleaved evergreens continually drop leaves and grow new ones. Deciduous trees drop their leaves in the autumn or fall and grow new foliage in the spring. This is an important element to consider when we’re designing and deciding where we should plant new trees in the garden. For example, siting a pond under evergreens means that there will be the constant chore of removing leaves from the water so they don’t rot and affect the water quality.
The easy maintenance option where leaf collecting is concerned is more likely to be found with deciduous trees rather than evergreens. That way you may have two or three weeks when you have to sweep leaves off the lawn and patio, but for the rest of the year there will be negligible leaf fall.
What is a Tree Preservation Order?
A Tree Preservation Order has been made in order to protect a tree which brings a “significant amenity benefit” to an area. It can apply to trees in the garden as well as to street trees, trees in parks and woodlands; to individual trees or to a group of trees.
It is a criminal offence to cut down or even prune trees which are protected by a Tree Preservation Order without prior written permission from the Local Planning Authority. There are a few exceptions, for example, in relation to trees which constitute a risk, although written notification needs to be given of such work.
Whilst most people are aware if a single tree in their garden is protected, what many of our clients haven’t realised is that if their house is in a designated Conservation Area, then the trees in the garden are given automatic protection. Or to be more precise, any tree over 75mm in diameter at 1.5m above ground level is given automatic protection. Fruit trees are exceptions, in so far as the regular pruning of them “in accordance with good horticultural practice” is allowed.
At Plews we keep up to date with these and other laws which are likely to affect our clients and any works in their garden; whether that relates to trees, changing the levels in the garden, or paving over of front gardens. We offer advisory visits and reports as well as considering all these aspects when we are designing and landscaping your garden for you.