Some trees will busily grow all summer and in most seasons keep on producing fresh leaves and shoots. Others such as oak and horse chestnut tend to produce a first flush of leaves and then, around June, stop growing. Their fresh shoots produce sugars that are stored for the winter but if the weather is dryish no further new growth is made. However if the weather is wet the trees suddenly start into new growth again, giving a spring like fresh green hue to the oak woods. This traditionally occurred around late July and early August and was known as Lammas growth because it was close to Lammas day. This day - 1st August - was a traditional day of celebration dating back many centuries when blessings were sought for the harvest. The word Lammas was derived from the Anglo Saxon Hlafmaesse which roughly translated means loaf mass.The very first ripe cereal grains were collected and bread baked from them,then crumbs from the loaf were sprinkled in the corner of barns to bring luck for the coming season. In our rather dry area Lammas growth is rare but this year the oaks could not wait for Lammas day, they burst into new growth in early July - so they have only briefly paused in their growth. This is good news for the Curry Woods as the newly planted oaks will not only produce plentiful new shoots and leaves but below ground the roots will be expanding through the damp soil much more easily than if it had been a dry summer. As roots push their way through the soil using hydrostatic pressure dry weather baulks their progress in two ways, firstly hard dry soil is much more resistant to small roots and secondly the roots cannot take on board enough water to grow and expand. All root growth depends on the simple physics principle that liquids cannot be compressed - so hydrostatic pressure is very powerful in pushing through solids and gases, both of which compress. That is why roots are like JCB earth moving machines (other makes are available) as both rely on hydrostatic pressure to move solid material like soil. Roots grow by their cells dividing and the new cells filling with water and pushing aside the soil. This is so much easier when the soil is wet and roots grow fast as they experience little resistance. This opens up many tiny channels in the soil and in the winter much more rain is absorbed by the soil than without trees - which is why our trees will play an important part in the future in retaining flood water that would otherwise run off towards the village!.
Above, a Rowan, that grows throughout the season and below, an oak showing Lammas growth