Fwd: ALIEN plants – how did they arrive in India? : 1 post by 1 author.
Following my recent post about ‘Aliens & Adventives’, I wish to comment further, raising the question of HOW are such plants spread?
In GCSE Biology in the UK students are taught about means of seed dispersal. Such methods – whether by wind or birds (who e.g. might each berries and then these are spread in their droppings) focus on dispersal in the same country. To answer the above question, one is MOSTLY considering species arriving from other countries especially, perhaps, those NOT bordering India.
And we are not just considering which species have arrived SINCE Indian Independence or those which were brought in during the British times.
I regularly give digital presentation about flowers in Kashmir to audiences in the UK. Included are a number of slides of the Moghul Gardens. Some of the well-known varieties are what we would call in the UK “Cottage-Garden” border perennials – no doubt some of which were introduced during he British days. However, quite a number of plants seem to have been introduced into Kashmir during the Moghul days – so hundreds of years ago. I understand that Shalimar was constructed in 1619 (or probably construction was begun or completed that year).
And we should not forget that such ALIEN plant species are not always insignificant curiosities, they can have a MAJOR impact on natural environments especially those which become INVASIVE WEEDS.
Also, it works the other way. ‘Himalayan Balsam’ (Impatiens glandulifera) has become an invasive weed in parts of the UK and has spread to Europe (as far as the arctic circle in Norway) and to North America (as far as Alaska).