The Orchid Ecology of Cromwell

I thought I would just add a piece on Orchid reproduction as relevant to Cromwell Bottom in view of a recent misconception by a Wildlife Group Member

Orchids reproduce using two potential processes -  vegetative multiplication and sexual reproduction. The degree to which different species of orchid are dependent on each of these processes varies widely.

Successful orchid seed germination requires the correct conditions to be present. Important environmental factors for orchid seed germination include moisture, oxygen, light and warmth. Orchid seeds also require the presence of mycorrhizal soil fungi for successful germination and growth. Mycorrhizal soil fungi are often present in healthy unimproved and undisturbed soils. 

Orchid seeds carry no food reserves   , the nutrients they require to germination and growth are   provided by the fungus. The relationship between developing orchids and mycorrhizal fungi is at first parasitic, but as orchids mature their dependence on the fungi decreases. The extent to which the mycorrhizal infection continues after an orchid reaches maturity is species specific. Some orchid species eventually expel the fungus, while others retain it.

Once infected with the mycorrhizal fungus the germinated seed develops in to a tuber. Once the tuber reaches maturity it produces leaves. These leaves feed the developing orchid tuber for several growing seasons until the orchid has stored enough energy to be able to produce flowers. These flowers attract specific insect pollinators to facilitate sexual reproduction and seed production.

The Ecology Of Cromwell Bottom

Orchids generally favour crude disturbed soils and the ruderal conditions on the capped tipped waste site of  Tag Loop provides aspects of this . The variuous soil moisture and temperature gradients  achieved on the slopes and bleeds into pockets of richer soil  can mean that distributions and densities vary. It is likely where crude soils exists with little sub soil bacteria or humic matter these densities result in vegetative multiplication equally there are areas in the reserve where beneration is by seed germination . There is no exact science here and further observations will provide valuable knowledge into establishing sucessful and sustainable orchid populations on the North Loop. As a generalised statment I suspect Orchid clsuters  found along the river on bankings are predisposed to seeding due to richer soils and those on the harder crude  clay vegetatively.
So before alterring the environment understand it !! 

Orchids

Common Spotted Orchid
Early Purple Orchid

Broad leaved Helleborine

Follow The Countryside Code

• Please stay on the paths provided.
• Please do not pick flowers.
• Please keep your dog on a lead and shut the gates when you go in and out of  the reserve.
• Please don’t leave litter.
• Becoming a Trust member or making a donation will also help us to continue to protect the orchids into the future.