Canadian sap-eaters, butter brimstone, sourdough for marmalade

Planting trees with dibber and tang

Trees are magnificently complex systems. The tree has an up and down elevator. The up elevator is the sap layer surrounding the heartwood. It is called xylem. It carries water from the soil via the roots to the leaves.

Together with carbon dioxide from the air and energy from the Sun, the tree makes glucose and oxygen in the leaves. The oxygen enters the air, and the glucose goes down the down elevator (the inner bark called the phloem).

The sugar-laden sap tastes good. Some humans eat it. They are called Canadians. There are a few Canadians in my family. They love pancakes for breakfast and they smother them with tree sap (that is maple syrup).

A bare-root whip is a young tree, about two years old. We planted just over 200 recently. They were alder buckthorns.

These trees are one of only two tree species that the brimstone butterfly caterpillar loves to eat, the other being the common buckthorn.

There is a view that the word 'butterfly' originates from the yellow colour of male Brimstones. The wings of the female are very pale green, almost white, males have yellow-green underwings and yellow upperwings.

Source https://butterfly-conservation.org/butterflies/brimstone

The pale yellow-green of brimstone butterflies is similarly beautiful to the sulphur quartz that they are named after. They look like the leaves of the plants that they inhabit like alder buckthorn and ivy.

The whips were planted in small plantations on the bends in a lovely small river. The intention is to prevent erosion of the river bank as it meanders.

They were planted together with hawthorn, blackthorn and spindle, which are all twiggy, woody trees that make a good hedge. They attract pollinating insects, bees, and birds like thrushes, redwing, fieldfare, and finches. The hawthorn attracts wood mice and slow-worms, the spindle attracts magpie moths, spindle ermine moths, scorched wings, and holly blue butterflies. The blackthorn is popular with hairstreak and swallowtail butterflies and many species of moth caterpillars.

Some crack willow has been planted in these plantations. These will grow tall. In windy conditions the branches crack noisily and fall.

The fallen branches can float downstream and get lodged in the bank and grow into new trees.

Several passers-by stopped to ask us what we were doing. I met Peter who shared his beautiful photos of the local river taken at sunrise and sunset.

I will explain what a dibber and tang are, in case you don’t know. A dibber is a special spade that foresters use to plant small leafless trees (called whips).

The dibber has a kind of foot-rest called a tang. The idea is that the tool cuts the soil, so that the whip can be be inserted, burying its roots.

While planting, we added a soaking of living nature called compost tea (a special concoction containing mycorrhizal fungi). I think of it like the tree’s power-breakfast of sourdough toast and marmalade.

The Royal Horticultural Society has this to say on the topic:

Mycorrhizas are beneficial fungi growing in association with plant roots, and exist by taking sugars from plants ‘in exchange’ for moisture and nutrients gathered from the soil by the fungal strands. The mycorrhizas greatly increase the absorptive area of a plant, acting as extensions to the root system.

To grow well, plants need a wide range of nutrients in various amounts, depending on the individual plant and its stage of growth. The three key plant nutrients usually derived from soil are nitrogen, phosphorus and potassium, while carbon, oxygen and hydrogen are absorbed from the air. Other vital soil nutrients include magnesium, calcium and sulphur.

Phosphorus is often in very short supply in natural soils. When phosphorus is present in insoluble forms it would require a vast root system for a plant to meet its phosphorus requirements unaided. It is therefore thought that mycorrhizas are crucial in gathering this element in uncultivated soils.

So now you know :-) about tree plumbing!

The fungi are little traders — exchanging water and micronutrients for sugar. Sourdough for marmalade, kind of!

The system pays off because those fungi are hanging out between the soil and the root tips. Root tips hold starchy sugar stores, like a squirrel stores acorns.