THE GARDEN AND FIELD. 



407 



lia. On this tree there were 315 

 WossiMus but oiil^- live set Iriul. 

 Other trees of the same variety 

 aloti<jside set the usual v-rop. Vet 

 Hen Davis is known to be a scU- 

 fertite variety. Such instances 

 could be duplicated nmuy, times 

 from the experience of every horti- 

 culturist who has in\-esti|>atcd this 

 subject to an^• extent. On the 

 Geneva Station this year sacks 

 were placed on the blossoms of 60 

 varieties, from ten to twenty sacks 

 being- placed on each tree. Toiman 

 Sweet, which is sometimes classed 

 as a self-sterile sort, set sieven 

 fruit in one. sack. Oldenburg, which 

 is known to be self-sterile, gave no 

 fruits whatever, although the 

 twigs surrounding the sacks were 

 co^erefl with fruit. The re- 

 sults of other varieties were equal- 

 ly confusing. Such experiments 

 as this are not worth publishing ; 

 all that they indicate is that sack- 

 ing alone will not determine for 

 the apple, as it does for the grape, 

 w^hether the variety is self-fertile 

 or self-sterile. The question na- 

 turally arises why is it that a 

 variety normally self-sterile should 

 fail to give fruit, under sacks. It 

 manifestly must be on account of 

 some abnormal condition produced 

 by the presence of the sack. A 

 manilla sack being close and imper- 

 \-ious, will naturall}- shut out 

 more or less of both light and air, 

 but the same is not tisjve otf muslin 

 sacks, yet they give the same con- 

 tradictory results as the paper 

 ones. In Low^e and Parrott's ex- 

 periments, where they covered 

 small trees or large branches with 

 muslin, windows were made of 

 wire screens for the admission of 

 light and air. In no case did they 

 llnd that there was any more fruit 

 close to the w-indows than away 

 from them, and there were no 

 iriore fruits in the muslin sacks 

 with windows than in those with- 

 out. So it seems that it can 

 hardly be a question of the lack of 

 light and air. In putting a sack 

 over a cluster or several clusters 

 of blossoms it is ver^^ difficult not 

 to have the sides of the sack so 

 close to the blossoms that the na- 

 tural movernent of the sack in 

 wind would cause it to press 

 against certain of the stigmatic 

 surface after the petals have ex- 

 panded. It seemed a queption as 

 to whether this possible injury 

 might prev^ent fertilization from 

 taking place. Examination of a 

 large number of sacked blossoms, 

 however, failed to show that there 

 was anv greater probability of the 

 fruit that set being in the centre 

 and more protected than in the 

 outer portion of the sack. This 



year four fruits were found, each 

 in dilTerent sacks, where the sack 

 ha<l l>ccn i)ullied down on the 

 branch so far that the blossom 

 was bent back upon itself so that 

 the calvx end of the fruit pointed 

 down upon the l)ranch upon which 

 it was borne. Vet fruit had set 

 under these conditions. In numer- 

 ous other cases fruit had set w th 

 the cahx i)ressiug against the 

 sitles of the sack, showing that the 

 contiquity of the sack apparently 

 had no deterrent effect on the 

 setting of fruit. There seems to 

 be only one other abnormal condi- 

 tion produced by the sacks, and 

 this is the prevention of insect 

 \isits. The use of the sacking 

 method as a means o£ determining 

 a fruit's capacity for self-fertiliza- 

 tion is leased on the supposition 

 that it will prevent insects from 

 bringing i)ollen of other varieties 

 while the pollen of the blossoms 

 enclo.sed will fall on their own 

 stigmas. So far as I am aware, 

 it has never been proved that this 

 is actually the case. The stigma 

 of the apple is receptive, even be- 

 fore the blossoms open. If blos- 

 soms are castrated the day before 

 they normally open and pollinated 

 at the same time, they will usu- 

 ally set fruit. How long thei stig- 

 mas remain receptive I do not 

 know, but I have never found as 

 good results from the later pollin- 

 ations as from the earlier ones ; 

 apparently showing that the recep- 

 tive condition is not long con- 

 tinued. When the blossom opens 

 the anthers usually have not burst, 

 and no pollen is ayail'able from 

 that blossom. They soon com- 

 mence bursting from the outside 

 in, that is, those at the periphery 

 dehisce first, and then those to- 

 ward the centre. Thus it will be 

 seen that the chance of the stigma 

 being past the receptive condition 

 before the closest stamens would 

 have available pollen is very great, 

 and that pollen from other and 

 earlier blossoms would, be neces- 

 sary in order that fertilization 

 should take place. 



— The Reason Possibly a Mechan- 

 ical One. — 



A consideration of these facts 

 makes it appear possible that the 

 reason why apple blossoms seldom 

 set fruit under sacks as readily 

 as they do outside, is a mechanical 

 one and due to the pollen not be- 

 ing on the legitimate surface at 

 the proper time. I have been con- 

 firmed in this view by the finding 

 in one orchard this year ■ that in 

 every case where fruit had 'set in 

 the sacks, the apple aphis was 



present, al.so. These sacks w«re 

 wired to the twigs, and while it 

 might l)c possi])le that an aphis 

 could crawl through the ojjening, 

 it does not seem possible that it 

 could do so with pollen sticking to 

 its body without the ixdlen being 

 rtibljcd off. This coincidence was so 

 marked that it was possible to tell 

 whether there were apples in any 

 particular sack by tearing ofi the 

 bottom of the sack and lof)kiug for 

 the cast skins of the aphis. If 

 these were present, then, the fruit 

 could be confidently looked for. In 

 one case there were seven fruits m 

 one sack, the variety being Tol. 

 man Sweet, which as is mentioned 

 abo\-e, is sometimes listed as be- 

 ing self-sterile. For these reasons, 

 and others which the length of 

 this paper will not i)ermit me to 

 elaborate, I am strongly of the 

 opinion that we will never secure 

 satisfactory results from sacking 

 apples except where they be also 

 hand pollinated with their own pol- 

 len. This manifestly is going to 

 add very seriously to the labor of 

 all such investigations. — "American 

 Horticulture." 



. ^ 



Revenge is chiefly a function of 

 memory, and with the majority of 

 mankind, forgiveness Is but a 

 form of forgetfulness. Be very 

 chary, therefore, of ofiending those 

 persons who jiossess good mem- 

 ories. 



ALSTON'S PATENT STEEL 



JAMES ALSTON, 



Queen's Bridge;, IVSelbourno. 



Sol* AgKits for South Au8irai>:>~ 



H. C. RICHARDS 



6 aod 8, Bljth Stre«t, Adakid*. 

 date Oi.ben>» tnd Co. 



