Magnificent trees

Saving species
In botanical terms, Bicton’s extensive collection of coniferous trees from around the world has been the most important part of the gardens since the Pinetum was laid out in 1839. Its scientific significance was heightened by the arrangement of plants in taxonomic order, so that groups of related species could be seen close together.
This strict order can pose problems with the likes of variable diseases that prefer certain species and fortunately the order has been lost over the years due to the planting of readily available trees in place of rarer specimens that have died or been blown down. Today, the resulting mix has made the park more attractive, and future plantings will take aesthetic appeal into account while restoring the original plantings where possible.
Large storms hit Bicton in the late 20th century resulting in 79 trees destroyed in 1976, and 67 in 1990. Few of these were replaced until 2000, when more than 50 saplings were planted in the Pinetum as part of an ongoing conservation programme. Gene-pools held across the world at botanical gardens are an insurance against disaster in the wild, where an increasing number of conifer species are under threat.

Tribute to Wilson
The Pinetum was extended to 16 acres in 1910 by the addition of the Lower Pinetum, also known as the Wilson Collection. The name derives from the great plant collector Ernest Wilson and includes a number of conifers collected in China specifically by him. One of the trees, Wilson’s spruce (Picea wilsonii), was named after him.

Biggest, tallest, oldest
Bicton is home to multiple Giant and Coastal Redwoods that have reached heights of over 40m (131ft) but even these monumental trees are small compared with their wild counterparts on the Westcoast of the USA. A Wellingtonia or Giant Redwood (Sequoiadendron giganteum) known as The General Sherman in California is the largest living thing on the Earth with a diameter of nearly 8m and height of 84m. Coastal redwoods can grow even taller with Hyperion measuring at an astonishing 116m. The Pinetum also contains a national champion Mexican white pine (Pinus ayacahuite var. Veitchii), that produces huge white tipped cones that can sometimes measure 50cm in length.

Trees of the Shogun
Bicton is host to all of the ‘Five Trees of Kiso’, which are Hinoki, Sawara, Asunaro, Nezuko and Koyamaki. After heavy logging these valuable timber trees were specially protected by the Shogun rulers of ancient Japan with strict rules and deadly consequences suggesting a tree was worth a humans neck and a branch worth an arm.

Botanical sensation
Of the 630 or so species of conifers world- wide, only 17 are deciduous. This small group comprises six genera, all of which are representedat Bicton by trees such as European larch (Larix decidua), the American swamp cypress (Taxodium distichum) from the Florida Everglades and four Chinese species – golden larch (Pseudolarix am-abilis), dawn redwood (Metasequoia glyptostroboides), the extremely rare Glyptostrobus pensilis, and the curious ginkgo (Ginkgo biloba), which is classed as a primitive conifer despite its broad, fan-shaped leaves.

The dawn redwood caused a botanical sensation when it was found to be growing in China in 1941. It was previously known only from fossilised remains and had been considered extinct for two million years. Like the other deciduous conifers, it produces outstanding colour before shedding its leaves in autumn. Similarly, in 1994 the Wollemi Pine was found in a remote region in the Blue mountains of Australia after it was though to be extinct. Both of these trees can be seen at Bicton as rather impressive specimens.