Welsh Oak is said to be taller and more upward stretching.
The English Oak is said to be broader and spreads more.
However, how the tree grows has a lot to do with the density of its planting. A single tree in the middle of a field will stretch out sideways, its fellow in a dense wood with shoot up (slowly) to find the light!
Large, old, spreading oaks have a tendency to split their crowns, so heavy are their outward stretched arms so they have evolved to rest their lower branches on the ground. This can annoy some gardeners who worry that the weight of these will actually cause the crown to split and they are tempted to cut them off, often also in the name of aesthetics, tidiness and ease of mowing.
The head-gardener at Cholmondeley Castle knows how to treat his charges — this wonderful old fellow is starting to rest more of its weight on its elbows.
Another bugbear of mine is ploughing around oaks — those wonderful freestanding old trees in the middle of fields of wheat, oilseed rape or pasture — it is sad to see them stunted and struggling in areas where farmers plough right up to the trunks, disrupting the superficial rootlets and associated fungal hyphae. Farmers who understand their trees leave a good wide area around them undisturbed and you can see the difference.
These great solitary oaks can live for hundreds of years, providing homes for all sorts of creatures and shade for stock — they are worth nurturing!
dianaashworth 
Interesting! I didn’t know about the different leaf structures and shade. Hope you aren’t snowed in. Brenda X
Thanks Brenda — getting my jab today!
Yet again a wonderful sideways look at life in the country. In Montgomeryshire we have wonderful hanging oak woods that hang on to the sides of the valleys, and are of course sessile oaks.
Thanks Tim –these days when we walk more slowly up the steep hill opposite, I often think of two octogenarians and the bull dog who did the same and have left their imprint somehow.
Very interesting. The oak in our garden in Stevenage, is more upright than it should be, following years of attack by previous tree surgeons! My vegetable patch at the bottom of the garden, confirms it is an English Oak, as it is rather too well shaded! Having said that we love it and its associated wildlife including a mix of grey and black squirrels. These were first spotted in Letchworth Garden City, the next town north from here. We also frequently hear a woodpecker, which I have never managed to spot on the tree, but have seen on our fence!
Have been thinking about a woodpacker blog as we have more than ever this year — they are very partial to fat balls! Heard the first drum on the 6th!