By S.A. Calton
A casual winter visitor to the Ouse Washes could be forgiven in thinking that the vegetation consists entirely of various grasses and 'reedy things'. Return visits in spring and summer will show how wrong this assumption is. There is a wealth of plant life in, on and around the waterways and dry summer-land of the Ouse Washes.
The winter birds attract most human attention, but it is the summer plants that dictate what food supplies will be available for the almost exclusively herbivorous avian visitors, in both the winter and also the breeding season.
Although, unfortunately, some washes in the past have been ploughed and re-seeded with commercial varieties of grass, many have never seen such barbarism. The latter display a fantastic variety of grasses alone - often the species count goes into double figures.
There are variations of flora depending upon the soil type, aspect, altitude (relative!) - hence wet/dryness, and the historical management regime of individual fields. In recent years, there has been an increase in summer flooding, and this has had a marked effect on the diversity of plant life, especially in the lower-lying areas. It has also prevented proper summer management, which again affects the botanical biodiversity.
However, all of these pale into insignificance when compared with what many now see as the biggest threat to this site of international importance: the waters that now flood the washes carry with them a massive load of man-made pollutants. There are over ninety sewage plants now discharging into the Bedford Ouse, and the phosphorous load in particular is wreaking great damage. The source of this is mainly domestic detergents and soaps.
Without management, the whole area would turn first to scrub willow and eventually through carr to woodland - floods permitting. Therefore, it is crucial to maintain the habitat by grazing with cattle, sheep and horses, and/or cutting for hay. Given that the primary role of the Ouse Washes is a floodwater storage reservoir, it is important that trees and bushes, which restrict the flow of water, are kept to a minimum. Livestock eat the seedlings and therefore keep grazed areas free of trees and bushes. In the past, especially, many more plants than the grasses were exploited, as it is hoped these notes will show.
There are literally hundreds of species of plants growing on the Ouse Washes, and it is not possible to show photographs of them all - yet! Where to start? With no apologies to systematic science, I have concentrated first of all on the ones I have taken photographs of !! They are the ones in the following table that are underlined to show links to pictures and/or more detailed information.Please note that the pictures may not be exclusively of a single species - in such a diverse habitat it is difficult to get such shots