Wind pollinated trees and hay fever

 As winter draws to a close I always look forward to the first hazel catkins, that signal a change in the seasons ......... but then, when spring finally does arrive, I remember that I suffer from hay fever. The early-flowering trees are wind-pollinated, producing vast clouds of sneeze-inducing pollen. 

Wind pollination is a chancy business and once the pollen is released it's rapidly diluted in the air, so the chances of an individual pollen grain landing on a female flower stigma, leading to the formation of a seed, decreases exponentially with the distance between then. So the only way to improve the odds is for trees to release great quantities of pollen

Male catkins of hazel.

Tiny, female stigmas of hazel

Male flowers of ash, about to open

Ash flowers, fully expanded

Silver birch male catkins, a major contributor to hay fever

Silver bird male catkins

Elm flowers. Before Dutch elm disease arrived, the bare crowns of mature elm trees were covered in a purple haze of flowers, a magnificent sight, now just a memory.

Most wind-pollinated trees produce their flowers on bare twigs, unencumbered by foliage that might hinder pollen release, but beech is an exception. It may be that beech bud burst is delayed because its foliage is very sensitive to late frosts. 

Evergreen coniferous trees like Scots pine tend to produce their male, pollen producing cones on the tips of their branches, well clear of the foliage, where pollen is easily carried away by the wind.

New Year Plant Hunt in and around Durham city today

A second day of New Year Plant Hunting, this time along the banks of the river Wear and along woodland edges and hedges. Nineteen species in flower this time, of which these are some of the most pleasing:

Alder catkins

Hazel catkins

Hogweed

Nipplewort Lapsana communis

Lesser celandine, flower petals eaten by a slug but very attractive variegated foliage.

...... and cowslip, flowering four months early.

The cowslip was on the Durham University estate, on the Mountjoy site, about 400 metres from an area that was seeded with wild cowslips about 20 years ago. Since then they save seeded themselves on various places, most likely with seed carried on feet of staff and students. This single flowering plant was amongst a population of over 50 non-bloomers, all with very vigorous new leaf growth, on a very sheltered grassy bank under an alder.

Easter Sunday walk along the river Wear

Probably the best weather that I can ever remember for an Easter Sunday. We took a walk along the south side of the river Wear, between Wolsingham and Black Banks plantation at Harperley.

Reassuring to find that the weird flower spikes of toothwort Lathraea squamaria were coming up again under the old coppiced hazels, where we've known them for nearly 40 years.

There's something vaguely reptilian about these parasitic flowering plants that siphon off all their nutrients from the roots of hazel.

You can read more about the strange physiology and folklore of toothwort by clicking here.

This is the plasmodial stage of the slime mould Reticularia lycoperdon [recently renamed Enteridium lycoperdon], probably only about a day away from turning into the sporulating stage. In the plasmodial stage it creeps over the alder tree trunk surface, digesting bacteria, then it forms a parchment-like skin (for pictures click here) enclosing countless dark brown spores. When the skin ruptures they are dispersed on the wind, then germinate into minute amoeba-like organisms that eventually aggregate back into this creeping plasmodial stage, which is most often seen in spring.

I found my first wild primrose of the season growing at the base of an ash tree, and ....

... hundreds of butterbur flower spikes had appeared along the riverbank in the last week.

Elm flowers. A mature elm tree in full bloom was a wonderful sight, with its crown a haze of purple, but it's one we are unlikely to see again, thanks to Dutch elm disease. Young elm trees that have regenerated from the roots of dead stumps are common enough though.

The beautiful juvenile female cones of larch, waiting to be pollinated.

Artefacts of autumn: a hazel nut neatly split in two by a grey squirrel and the stone of a fruit (wild arum?) nibbled by a field mouse.

A rather tatty peacock that had safely made it through the winter and was sunbathing on an old plastic bag.

A pair of goosander on the river. Their behaviour changes in spring. A few weeks ago they would have flown before I could get close but once they are paired up and have identified a hollow tree to nest in they are reluctant to leave their territory.

A fantastic carpet of wild garlic leaves beside the footpath, that will become a sea of white in a few days' time when the flowers open.

Those trees at the top of the bank host a rookery, so we were accompanied by their cawing along this stretch of the walk.

Perfect weather for haymaking in Teesdale ...

    































 
Perfect weather for haymaking in Teesdale today .....

... turning hay to dry in dawn-to-dusk sunshine .....

.... and baling hay that was already dry .....

...... leaving bare fields that were full of hay meadow wild flowers a few weeks ago ....

     
































  .... but there are still mountain pansies flowering on the banks that are too steep to cut ....

.... and betony, a late summer flower of rough grassland and pastures, is in bloom ....

... with flowers that are almost as attractive as an orchid, while ....

    .... ripening hazel nuts are a reminder that autumn isn't far away ....

It's a catkin..... but not as we know it ...

I found this strange hazel catkin when I was out walking along the River Wear at Wolsingham at lunchtime. Unlike the normal one on the left, this one has branched into seven separate 'tails' at the tip. Might have been caused by damage during the very early stages of its development last summer.

Next Year's Christmas Card, an Early Spring and a Job Well Done .... ..........

While we were out walking in Teesdale this morning we encountered this very obliging Robin ...... 

.... that struck a variety of poses that might be suitable for next year's Christmas cards. 

 Incredibly, hazel catkins are coming into bloom along the River Tees near the Meeting of the Waters. With a mild weekend forecast they look like they'll be shedding pollen in the New Year. Strange days indeed.....yesterday we saw lesser celandines in bloom in Sunderland (but I forgot to take a photo). 

Meanwhile, lambing will begin in a few weeks. We spotted this magnificent ram in a field of sheep, with a contented look on his face that suggests a job well done....