MISSOURI BOTANICAL GARDEN BULLETIN 147 
at the top for the insertion of a sponge containing the ether, 
this opening being afterward sealed. The time of exposure 
is variable, the usual time given being 48 hours, but decreas- 
ing late in the season. Sometimes a second exposure of 24 
hours is made after a few days’ interim. ‘The treatment 
should always be given during the day, as artificial light 
may cause the mixed ether and air to explode. 
The herbaceous perennials and biennials are forced in a 
manner similar to the shrubs, and may be planted in beds 
or potted after several frosts in the fall. 
Bulbs are not forced successfully by means of etheriza- 
tion, because in practice they are gathered in late spring 
or summer and stored for months. After planting, the 
bulbs are allowed to remain in the cold-frame for a num- 
ber of weeks, so that when brought into forcing conditions 
they are well over the rest-period. 
The conclusions drawn from experiments and general 
practices are: 
1. Etherization reduces the rest-period. 
2. As a rule the greater the resistance of the dormant 
plant to growth under favorable conditions, the greater the 
‘advantage of etherization. 
3. The value of the treatment is decreased as the end of 
the rest-period is approached. 
4. Plants which respond readily to growth do not need 
any ether stimulation. — 
5. The expense of forcing is reduced in proportion to 
the length of time the plants occupy the greenhouses and 
the lower temperature necessary. An early market and 
better quality are also conducive to greater remuneration. 
LIST OF PLANTS FOR FORCING 
SHRUBS AND TWIGS 
Botanical Name Common Name 
IE WOON 55 Se NC) pares ies eG Vy ee che BLE 
Cercis canadensis .......... Sera ee ere Wea teecs Judas tree 
Cpaemwn Mebeios oe a Japanese quince 
cl dhe on dE insinfhcy ER CE EO ee ee .....Flowering dogwood 
ERT Orlane. 6 ae a a Slender deutzia 
ROOM POIRIER oe 
Diervilla florida ...... Fe cpa Oe Pa ge Sees Weigelia 
MMOCNOTEN OTANMIIONE © 6 ia ti ks Pearl-bush 
_ Forsythia viridissima ........ Dee ewes ee es Golden-bell 
Kalmia latifolia ...... pis eas co Pee RS ee ae Mountain laurel 
Lonicera tatarica ............... Heer are ears oe Honeysuckle 
Philadelphus grandiflorus ...... rere Cia tegen Nene Wegher Mock-orange 
Prunus triloba var. plena.............. ..... Flowering almond 
