immunity. This is particularly true of Group IV in which L. auratum, 
L. formosanum, and L. japonicum are the most highly susceptible that 
we know, while L. canadense and L. superbum can stand a fairish 
amount of exposure. Now and then we find individual clones that 
show a real degree of resistance. 
Mosaic is spread from one plant to another ONLY by means of a 
small group of sucking and chewing insects.-It does not travel through 
the air or soil. Aphis are the principal culprits. The farther north one 
goes the fewer aphis one finds. At Sandyloam we have none. We be- 
lieve that our only mosaic carrier is the potato leaf hopper. The insect 
carriers are almost invariably wind blown or crawling and conse- 
quently do not tend to travel very far, not more than 30 to 50 feet in 
the garden. 
With this knowledge as a basis the gardener can order and plant 
his lilies with more understanding and with relative safety and con- 
fidence. Lilies from Groups I and II are completely reliable. They will 
never perish from mosaic, and they can be planted any place without 
fear as to their susceptibility. 
The lilies in Group III can be ordered with a good deal of con- 
fidence. They are all of them first rate garden lilies and even if infect- 
ed with mosaic will be excellent garden plants for many, many years. 
However, if a particular gardener wishes any one of this group of 
lilies in very special form, with a maximum of height and floriferous- 
ness he should buy clean bulbs, which we offer, and plant them at some 
distance from the lilies in Group I. 
Group IV is a quite different story. This small group has in it 
the lilies we must guard. If they were not so exquisite they would not 
warrant the special attention they require. But L. auratum and L. 
japonicum are so beautiful that most gardeners feel that the extra 
effort necessary to grow them well is justified. And too, their price is 
not so high but replacement is feasible every few years. If these 
lilies are to last in the garden more than a year or two they must be 
kept at a safe distance from all lilies except those in Group II. A 
distance of 30 to 50 feet from infected plants is recommended. (This 
you will remember is as far as the carriers are apt to travel in the 
garden.) The group does especially well when planted alone against 
shrubbery. 
It is our opinion that the average gardener will find it very much 
simpler to plan his plantings in terms of getting along with mosaic 
than it will be for him to try to eliminate it altogether. Our own 
losses from mosaic are always negligible because we follow the cul- 
tural program we recommend for the gardener. But we do have some 
losses now and then and the gardener in turn should expect to have 
to make some replacements from time to time. We use every precau- 
tion to see that the bulbs that we send out are clean. We isolate by 
planting in cloth houses, since our many thousands of lilies are plant- 
ed rather close to one another; and we spray regularly with nicotine 
sulphate to control the carriers. When you order lilies from us from 
Groups II, III, and IV you may expect clean bulbs, though we have not 
felt justified in issuing a blanket guarantee that they are mosaic-free. 
That would require laboratory testing of every individual bulb before 
shipment. Most of the lilies in Group I that have had mosaic through- 
out their history, the Madonnas probably from Biblical times, are in- 
fected in our plantings. But while every dooryard Tiger and umbel- 
latum has mosaic and thrives indefinitely, we are slowly building up 
some clean stocks of these particular lilies for the handful of mosaic- 
free gardens which exist in this country. 
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