Good find! And a useful reminder that in the UK at least, it's worth looking out for wild hops.
Just thinking about where they might have come from - I don't know much about the Berkshire hop industry but in general there's been very little commercial growing outside the main Kent-Hampshire strip and Hereford & Worcester (plus a bit around Nottingham back in the day) - like a couple of dozen acres in the whole of the rest of the country. Might have been a bit in Berks in the heyday of the late 19th century, but it wouldn't have lasted long. However
this 1813 survey suggests that there had been "considerable quantities" in Berkshire in the 18th century "and now grow naturally in the hedges in many places"- presumably improving transport links allowed Kent/Hereford to kill off the local trade, whilst the population needed for harvesting got sucked into the towns.
So, we're probably looking at very old 18th century landrace-type varieties rather than anything more modern. So expect low alpha.
It can be quite difficult to identify hops by cone shape and leaf, but the colour of the mature bines is useful. The ones you're looking out for are green bines with red mottling or red pinstripes - Goldings - and green bines with red leaf stalks, which are almost certainly Fuggles. However, the one on the gate looks a pretty obvious red bine. Traditionally they were very much considered the second-line, "quantity over quality" hop - a typical example is the Tolhurst I brewed with earlier this year, although that wasn't selected until the 1880s. The USDA's sample of Tolhurst came in at 2.2% alpha, although if you read the old Wye annual reports they seem to come in at about 4%. This is perhaps the
definitive report on brewing with Tolhurst.
So don't get your hopes up!
Bearing in mind that I was using 2017 hops which across the UK was not a great year thanks to the dull summer (this year should be more citrussy), Tolhurst cones smelt nice and citrussy on the rub, but just rather disappeared in the beer. Historically they did have some use where a preservative effect was needed from their high betas, without too much of a flavour contribution. So things like milds and Victorian porters; I guess they could be used for eg lambics. But you're welcome to try them in a SMaSH just to see what they're like? Or just use them as decoration....
Usual comments about green hops apply - if you're going to use them as green hops, then use them within hours, the unique flavours go off really quickly. And since the USP of green hops is all the volatile compounds that normally get destroyed by the heat of drying, you get the most out of them from using them as whirlpool/dry hops, never mind the uncertainty you have with alpha. But hey, they were free, so do as you will.
