384 
Whether Zizania aquatica is capable of establishing itself 
permanently in the British Isles is uncertain. From time to time 
surplus plants have been planted on the banks of the lake and in 
the ha-ha which separates the Kew Arboretum and the Queen’s 
Cottage Grounds from the banks of the Thames, and left to take 
their chance; yet although they have often grown and flowered 
well, I have never seen a single plant the following season. Still, 
circumstances at Kew are not favourable for an experiment of this 
kind. The lake and the ha-ha are emptied of water and more or 
less cleaned every winter, and unless protected, both the seeds and 
young seedlings are exposed to the attentions of the ornamental 
water-fowl. But even in the Lily Pond, where the plants have 
been watched and guarded, our experience has not been particularly 
encouraging, for when left to itself the Zicania has rarely survived 
more than two seasons. A considerable quantity of ungathered 
seeds fall into the water every autumn, which germinate freely 
enough the following spring, but so late are they and so slowly do 
the plants grow in the early stages that they appear to be unable to 
pore good seed, except after unusually long and warm summers. 
t is for this reason that we find it necessary to raise young plants 
under cover, and to hasten them through their early stages as 
described above. Lord Walsingham, who has grown the Zizania 
at Merton Hall, Thetford, in Suffolk, for some years, informs us 
that his experience in this respect is similar. 
on the margins of the western lakes, and in the backwaters of the 
rivers, where the soil and depth of water are perfectly suited for 
the Zizania. There remains, however, the important factor of 
climate, and especially sunshine. The plant grows naturally where 
the winters are severe and the summers very hot. Our winter 
conditions are quite favourable ; for the seeds, as has already been 
stated, can pass through the winter months embedded in ice. It is 
: =< of summer heat that the difficulty will probably be 
ie. 
