On the 31st January, I undertook the RSPBs Big Garden bird watch. Most birds, I’d normally see, were clearly hiding but I did notice some within the hour. Those birds I saw were; 1 Carrion crow (Corvus corone), 2 Robins (Erithacus rubecula), 1 Coal tit (Periparus ater), 1 Blackbird (Turdus merula) and 2 Mistle thrush (Turdus viscivorus). I enjoy taking part in this citizen science project each year; it’s interesting to see how the results differ each time.
Due to the frozen ground last week, I was still able to go for my regular exercise in the local woodland park. Various tree species were waking up from their winter sleep. Beech (Fagus) and Oak (Quercus) had started budding while others were developing catkins.
As well as the Hazel (Corylus avellana) other trees had catkins hanging from them too. Hazel catkins are the earliest to flower in the year, from January to March (see my previous post A Snowy Adventure).
Then the Alder (Alnus glutinosa) is the next tree to bloom with both male and female catkins. The male catkins are longer than the female ones which flower from February to March. Also hanging from the Alder trees were some small dark brown shapes. These woody cone-like fruit develop from the previous seasons fertilised female catkins; these can remain on the tree (even when the seeds have been shed) well into the following year alongside the newly formed catkins. I also noticed leaf buds growing on the trees last week too. When the buds burst, I shall update the Woodland trust Nature’s calendar with my findings.
Unfortunately I was unable to capture decent photos on location so I collected part of a fallen branch to take home.
I find Alder trees fascinating and the rough, fissured bark beautiful.
Alder are native to Britain and found on wet land, next to water or in marshes and woodlands. They naturally thrive in moist conditions although can also grow in drier areas such as the edges of mixed woodland. Alder wood is durable when wet and actually becomes stronger rather than rot when submerged in water; a characteristic that makes them useful in flood mitigation, boat building, sluice gates, and even the construction of Venice which is mostly built on Alder piles. Alder wood is also used in the creation of charcoal, gunpowder and making clogs.
The pale wood turns a deep orange colour at the point at which it’s cut (while the rest of the wood remains pale); leading to a superstition, in Ireland, that it was bad luck to walk past an Alder tree on your travels. However, traditionally alder branches were also taken into houses to prevent Woodworm. Alder wood is particularly liked by various species of beetle larvae (collectively referred to as Woodworm). It is hoped that the beetles will lay eggs in the Alder rather than the furniture or fixtures; the branches once infested can then be removed.
There is also a traditional use for Alder flowers as a green dye; believed to be used as camouflage by outlaws like Robin hood and fairies.
For fun, I looked up Alder wands used in the Harry potter series. Only one is mentioned, that owned by Quirinus Quirrell. The wands qualities are described on the Wizarding world website.
The roots of Alder are nitrogen fixers. Nitrogen from the air is fixed into the soil, replenishing the levels and aiding soil fertility, through the bacterium Frankia alni.
As well as improving soil, Alder are great for wildlife too. The seeds are eaten by Redpoll (Acanthis flammea), Siskin (Spinus spinus) and Goldfinch (Carduelis carduelis). The leaves are food for the caterpillars of the Alder kitten (Furcula bicuspis), Pebble hook-tip (Drepana falcataria), Autumn green carpet (Chloroclysta miata) and Blue-bordered carpet (Plemyria rubiginata) moths. Bees visit the catkins for an early source of nectar plus Alders provide habitats for the Checkered skipper (Carterocephalus palaemon) butterfly, Small pearl-bordered fritillary (Boloria selene) butterfly, some species of Crane fly, Otters (which create nests amongst the roots) along with mosses, lichens and fungi that like damp conditions.
However, these trees are also threatened through infection by the Phytophthora fungus (together with some other broadleaf tree species). In Alder this disease is referred to as Alder dieback and eventually causes the death of any infected tree. For more information see the Forest research website. There aren’t many Alders in my local woodland park compared to other tree species so it would be sad to see them disappear. Given my newly acquired knowledge I will keep a special lookout for any ill health in these trees; thankfully no infection is being exhibited at the moment.
Bee in the Moment 