Oak and ash

[BSHC]

Oak and ash

Oak before ash, in for a splash
Ash before oak, in for a soak

It will be disappointing to learn that there is no evidence linking the relative timings of oak and ash and subsequent rainfall.

Rather the relative timings are influenced by temperature with oak being more responsive than ash. This has been determined by the data being collected within the Nature’s Calendar project.

Using historical data from Norfolk (1750-1958) we have 158 years when both ash and oak were recorded. On 46 occasions (30%) ash was earlier.

More recently data from Surrey suggest ash earlier on only 3 occasions in 39 years, and in Northumberland only 3 occasions in 28 years.

In all instances oak gets more advantage over ash in warmer springs as shown in the following graph.
 

These patterns all point to the fact that it will become increasingly unlikely for ash to precede oak as the climate warms.

Woodland consists of communities of plants and animals that live in support of or in competition with one another. That oak is taking greater advantage of a warming climate suggests that there may be a change in the competitive balance in woodland in the years to come.

Interestingly there are similar rhymes about oak and ash in, at least, German and Norwegian:

UK
Oak before Ash, in for a splash
Ash before Oak, in for a soak

Germany
Grünt die Eiche vor der Esche
hält der Sommer große Wäsche
Grünt die Esche vor der Eiche
hält der Sommer große Bleiche.

Norway
Ask før eik blir steik
og eik før ask blir plask

But stranger still, these suggest the opposite relationship to the English rhyme.