The Hollies, Weetwood (North Leeds)

Saturday 24th February 2024

Leader: Graham Heffernan

Number of attendees: 22

The Group last visited this site in September 2022 when Graham led the annual autumn tree walk. Today, our focus was winter tree identification, using characteristics including buds, twigs and bark. Just over a week ago, Graham had led an indoor workshop on winter identification of broad-leaved trees, so now was our chance to put this learning into practice. It was a beautiful day to be out and about exploring the woods with sunshine and a blue sky, just warm enough to leave my hat and gloves behind. Graham was a fountain of knowledge on not only useful diagnostic characteristics of the various tree species we encountered, but also, for example, on their ecology, evolution and how they got their names. Other members also chipped in with interesting nuggets of information, adding to the enjoyment of the day. We proceeded at a very leisurely pace through the semi-natural woodland of the Meanwood Valley then crossed Meanwood Beck on a wooden footbridge and up the slope to The Hollies before retracing our steps. Here are a few of the things we saw today:

Graham pointed out Hazel (Corylus avellana) and Alder (Alnus glutinosa) both of which had catkins present. Hazel and Alder are members of the birch family which all have separate male and female flowers on the same plant. When ripe, the pendent catkins of male flowers release pollen into the wind. On one of the hazels we found the tiny ruby-red stigmas of the female flowers which emerge from bud-like structures along the twigs. In Alder, the female flowers develop into cone-like fruits which persist on the tree into winter, aiding our identification.

Willows and poplars also have catkins, however, unlike the birch family, the male and female flowers are on different plants, so each tree/shrub is either male or female. Graham showed us a Hybrid Crack-Willow (Salix x fragilis), in which it is possible to distinguish between the male and female trees by looking at differences in the buds. Our tree had buds curved to one side and were relatively large (wider than the twig) making it likely to be a male (the buds of female trees are not curved and only up to about 6mm wide (as wide as the twig).

Graham pointed out how the bark of tree trunks can vary not only between different species, but also with the age of the tree. Grey Poplar (Populus x canescens) and Goat Willow (Salix caprea) have distinctive diamond shapes on the bark.

Elder (Sambucus nigra) is one of the first trees to come into leaf and today we saw some newly emerged green leaves. Graham explained how bud scales are modified leaves, and in elder, these scales are especially leaf-like. We also stopped to admire the bright red young stems of a planted Dogwood (Cornus sanguinea). The name Dogwood is thought to be a corruption of ‘dagwood’ and derives from the use of the twigs as skewers or ‘dags’.

We looked at a few conifers and non-native plants at The Hollies. I particularly liked Graham’s description of the trunk of Western Red-cedar (Thuja plicata) looking like a cat has been using it as a scratching post (the soft red bark has a shredded look). A puzzling tree that was first thought to be Lawson's Cypress until we found that the crushed leaves smelled of citrus rather than parsley, was later confirmed by Graham to be Hinoki Cypress (Chamaecyparis obtusa).

Some plants were already in flower in the gardens including the large pink blooms of Rhododendron, the dainty white sprays of Osoberry (Oemleria cerasiformis) and slightly larger white flowers of Fly Honeysuckle (Lonicera xylosteum).

We ended the outward part of the walk looking at Spindle (Euonymus europaeus) and Walnut (Juglans regia). The usual green twigs of Spindle were mostly disguised by a covering of algae. We also had a fine vista of a row of planted trees as shown in the below photograph.

Text by Susan

Photographs by Susan, Tom, Alan and Ian B