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We were very lucky to welcome Greg Packman for our Winter Tree Walk. He surveys and looks after the trees in Alexandra Park. As well as giving us some great tips on Winter tree identification, he talked about some of the tree management issues in the Park.

We met up by the Park Visitor Centre for a quick briefing before looking at the Horse chestnut tree and its large sticky buds which may be a protection against insects tucking in.

Sycamore and Ash followed and with key points to identifying the trees in Winter - these trees have buds that come out "opposite". This means that there is always buds in pairs either side of the twig.

Greg then contrasted the Hornbeam and Beech trees - both have pointed buds, but the Hornbeam ones turn back into the twig whereas the Beech point out proudly. (left)

Stopping at a Holm Oak, he showed its clustered buds at the top of the twig (like all oaks). Then we looked at a Lime Tree in the Avenue and he explained a lot of the problems in managing such an avenue.

Other trees that we looked at were the large Veteran Oak and a Sweet Chestnut - the latter with its prominent lenticels. 

Also in The Grove there is a large dead standing tree (Sweet Chestnut?) showing a great example of cubical brown rot with Greg explaining its use in breaking down the wood and recycling nutrients into the soil.

Just outside The Grove, we looked at the fate of a Hornbeam attacked by Ganoderma residaceum (underside here) and a Sycamore killed by Soot Bark disease.

On the up side, we admired the Dawn Redwoods and Wellingtonias before finishing up by our leaning Cork Oak opposite the Palm Court.

Huddling in the protection of the Palm Court entrance with Storm Dennis bringing rain, we hoped that a few people would turn up for the walk. In fact an impressive 16 people met to listen to Professor Jeff Duckett explain about Bryophytes (Mosses and Liverworts).

We started off just looking some mosses on the stonework which included Tortula muralis and Grimmia pulvinata (pictured).

Jeff explained that mosses are on the come-back trail after the reduction in pollution, but also because of the increase in NOX emissions from cars (they benefit mosses). See his separate report here.

We wandered down and looked at the mosses on a Plane Tree and in the grass before crossing Alexandra Palace Way. There Jeff was slightly surprised to see moss on a Dawn Redwood, but pointed out an Ash which was expected to have mosses and showed how they specifically liked live in the drip line (where the water comes down the tree).

Walking along the Lower Path, we found a poplar with a nice collection of mosses on it including this Orthotrichum diaphanum.

In vain we looked bonfire sites which can be good for mosses, but apparently the Park had done too good a job clearing up!

We finally found a liverwort, Frulania dilitata, (related to, but different from mosses) on an oak below the Butterfly Meadow by which time the rain had called a halt.

More pictures from the walk here. - All Moss and Liverwort pictures here

The audience left the talk, by Andrew Wood from Hertfordshire Butterfly Conservation, much wiser on the habits and appearance of butterflies and moths: from what they eat (nectar and some rather less pleasant substances), to how they mimic other insects (including wasps and hummingbirds). Andrew posed and answered a dozen questions that revealed the amazing variety amongst lepidopterans. He also talked about how to improve habitats for butterflies and moths and the effects of climate change.

We had our annual stall at the Ally Pally Farmers's Market. The weather was quite kind to us with only a splash of rain. We recruited several new members and sold over 30 of our 2020 calendars.

The sellers were fortified by some left over mulled wine and mince pies.

We enjoyed our day at the market, a great asset to the park.