A pine cone is a reproductive structure, known as a strobilus. There are male and female pine cones. The male pine cones (or microstrobili) are less obvious than the female pine cones; they have a central axis from which project modified leaves - or microsporophylls; these produce pollen. Pine pollen is dispersed on the wind.
A female pine cone has a short stem, which attaches the cone to a branch, this continues through the central part of the cone (the rachis*). Scales arise in a helical manner along the length of the rachis to form the cone, accounting for much of its structuree and its characteristic, external appearance. Each cone scale carries on its surface two ovules, which on fertilisation develop into seeds - these are pine nuts. The scales are also known ovuliferous scales or seed scales. Pine cones take about two years to reach maturity. Read more...
Each year, a variety of conifers are sold as Christmas trees, for example, the
- Norway Spruce Picea abies
- Silver Fir Abies alba
- Nordmann Fir Abies normanniana
- Scots Pine Pinus sylvestris
and in North America
- Douglas Fir Pseudotuga menziesii and
- Balsam Fir Abies balsamea.
Oak trees are under threat through disease and climate change and it will cost serious money to research causes and solutions. This could be paid for either through general taxation or by an appeal for charitable donations with help from high profile people such as celebrities and the Royal family. The rate of required spending on oak disease is increasing. It is proposed to set up an "Action Oak" charity appeal spearheaded by Woodland Heritage - an organisation based in Haslemere just 10 miles from the Forestry Commission's research arm at Alice Holt in Surrey.
Many people will wonder why the government isn't doing more directly through DEFRA Read more...
It is now some 30 years since the “great storm’ which was (probably) the most ferocious weather event to arrive in the U.K in the last three hundred years. Winds that reached 115 mph wreaked devastation across the southern parts of the country. At the back of the weather front that brought this wind was a hook-shaped airstream - the “sting jet” which created particularly severe gusts of wind.
Eighteen people died; and the repair bill was probably in the region of two billion pounds. Amid the chaos of destroyed homes, blocked roads and railway lines, loss of power and telecommunications, it was estimated that some fifteen million trees were uprooted - in woodlands, forests, arboreta, parks and city streets.
That October was wet so the roots of trees were sitting in sodden soil, and the leaves were still on the branches. In consequence, when the gales / storm arrived the trees offered considerable resistance to the flow of air so that they were literally torn from the ground. It resulted in the loss of ancient (and modern) woodlands - and the damage to property and communications. Read more...
Research workers in the States and Germany have been investigating the effect of drought on the subsequent growth of various types of trees. Because of climate change, droughts are expected to increase in frequency and severity.
The workers in the States found that trees took between two and four years to recover from drought and resume ‘normal’ growth.
The reduction in growth could be due to Read more...
In Siberia, there are some indigenous peoples who continue to live as they have for hundreds or thousands of years. One such is the Evenks, who are nomadic and live off reindeer (both domesticated and wild) and they build a teepee-shaped houses out of wood and cover it in skins. When they move on they take the skins with them. They also have other clever innovations with could provide inspiration for the British woodland owner, such as a “fridge” built high up so as to be out of reach of animals, and they have clever animal traps made with logs. Some of these seem to be intended to crush the animal and others to trap it (images below).
One tradition they have is that instead of burning their dead or cremating them they leave them on high platforms so that the corpse can be eaten by birds. This particular idea may be less useful to the British woodsman and might even be frowned upon, especially in the Home Counties. Read more...
President Trump is concerned that the Paris Climate Agreement will damage the U.S economy, cost jobs and offer a competitive advantage to Countries such as China and India. In consequence, he has said that the United States will leave the Paris Climate Agreement and he has also ordered a review of ‘climate regulations’ legacy from the Obama administration. The effect of these policies will be the release of greater quantities of carbon dioxide into the atmosphere - which will further exacerbate global warming and climate change.
Building a log cabin in Siberia is an art that has been developed over hundreds of years and takes account of material available and the extremes of weather. For example, it may look as though the same logs are used for the whole cabin but in fact for the bottom three layers the Siberians use larch which is more resistant to rotting and carrying water upwards. Above that they use Siberian pine which is in much greater abundance - indeed its availability must be one of the reasons that so many of the buildings in Russia are built of wood, even today. Between the logs moss is wedged into the gaps to prevent draughts and to seal the building from insects. This moss, again, is freely and abundantly available in most of Russia. Read more...