THE ROCK FERNERY 59 



species. It is the knowledge of the habits of Ferns that 

 is of such great importance when planting ; for many of 

 the large-growing sorts have the appearance of being 

 fully developed while they are quite small. One guide 

 is that in many Ferns the appearance of fertile fronds 

 indicates that they will not get much larger, but this is 

 not always reliable, for some have fertile fronds in an 

 early stage, and others fail at any stage to produce 

 spores. It is only by experience that the habits of 

 various species can be ascertained. When grown in pots 

 they can easily be transferred, but some of the most 

 beautiful Ferns do not like being disturbed after they 

 are established on the Rockery. 



It may also occur that a good many Fern weeds may 

 spring up and choke out the choice sorts. Of all Ferns 

 Nephrodium molle should be avoided, for once this ripens 

 its fertile fronds, seedlings spring up in all directions. 

 Pter'u tremula is almost as bad. Gymnogramma Martensi is 

 another troublesome weed. 



It is often owing to the want of a little attention that 

 choice Ferns are lost. When they have been planted 

 for some time there may be some which will require 

 more fresh soil round the crowns. With the deciduous 

 sorts on the outside Rockery the old fronds should be 

 left on to protect the crowns. Slugs and snails often 

 prove great enemies on the Rockery, and must be looked 

 after. Inverted pots with any kind of green vegetable 

 under them make good traps. It will save much trouble 

 if they are caught before the Ferns start to make new 

 growth in the Spring. The tiny black slugs are the 

 most troublesome indoors, and if not watched they do 

 much mischief, the Aspleniums will suffer most. They 

 will eat the young fronds through just as they begin 

 to uncoil, and Adiantums often suffer very much. For 

 these small black slugs, carrots, potatoes, or turnips cut 

 in slices and laid about make good traps. 



