Professional Tree Services

Julian A. Morris B Sc, Dip Surv, Cert Pub Sect Man, Tech Cert Arb, PTI


Background photo - Junipers in the gardens of Le Corbusier's celebrated "L'Unite" building, Marseille, France 2008

September 2012 - Laburnum addict?

There aren't many trees in this country that are poisonous. One that has always been considered poisonous is the Laburnum. Yet, a review of the available facts about poisoning cases suggests that the worst that could happen to most people is to feel pretty sick or to vomit. Even then, such cases are usually in children, who have less body mass to spread the effect of the toxin.

The poison in Laburnum is cytisine. It is similar in its effects on the body and brain to nicotine, and is used in smoking cessation products as a nicotine substitute. Anyone who was pressurised into trying smoking when they were a teenager might remember as I do that the first cigarette just made you feel sick.

So, while reducing a Privet tree recently for a client, I was surprised to find this nest in it next to a Laburnum tree, chockablock with Laburnum pods which had had all the seeds removed. The nest was about 4 inches deep and had about 100 epmty pods in it. I had always assumed that if Laburnum is harmful to humans it would have a fatal effect on smaller animals or birds. The dexterity needed to extract these seeds suggests it was a squirrel that scoffed this lot of seeds.

laburnum nest 2

There are birds, mammals (e.g. sheep) and insects that are immune to cytisine It makes me wonder whether squirrels have the same immunity or whether the squirrel that dined on this lot died of poisoning. I also like to entertain the notion that the squirrel developed an addiction to Laburnum pods and had to return to this little smoking den frequently, whenever the craving came over him.