I'm moderately familiar with Westonbirt Arboretum, having visted it several times and across all seasons. It's most obviously spectacular in Autumn, of course, but it has its merits in all seasons. Capturing these merits in photographs is not easy, however. Woodlands do not easily provide potential images that fit the kind of rules that most people formally or instinctively use to choose good photos. There are three main options to deal with this - work really hard to frame images that DO fit the normal rules, go for detail rather than large scale or frame images that break all the rules but work anyway.
All three strategies are employed successfully here. The latter-most impresses me most of all. It's a good souvenir coffee-table book, set out in four sections, one for each season, starting with Spring. Howard's skill in taking successful photos in flat light or out-right misty conditions in the Winter section is remarkable.
Here's a few of my own efforts: