M()^■'l'lll,^ iu:i.!jEtix. 347 



all apples or potatoes wliich pass state inspection it is expected will 

 be of sneh a liiii:h s^-rade that inspection by comity officials will not 

 be necessary. For example, ai)plcs being shipped into the markets 

 of San Francisco. Los Angeles or San Diego, which beai- <iii llie boxes 

 a state standard label indicating that tliey have been packed according 

 to the high standards of the act, should be exempt from fiirther 

 inspection. It is doubtful if the exceedingly careful grading and the 

 high standard tiiat is being compelled, under the direction of the state 

 inspectors at Watsonville, is being maintained in many of rhi' sections 

 of this state or elsewhere, and recognition of the state label, as some- 

 thing that bears testimony to a splendid class of goods within the box 

 is something that is expected of the county horticultural commis- 

 sioners, and that their co-operation in this respect will l)e given is 

 not doubted. 



In the case of certified seed potatoes going into any county there 

 should be the same exemption from further inspection. Tliis com- 

 mission has hired the best potato expert that it is possible to find 

 in the state to pass upon certified seed, and nothing of a dangerous 

 character will be certified. There will, of course, be certified seed 

 that will need treatment with corrosive sublimate before plantiiiir, as 

 a small amount of Rhizoctonia, scab, or Fusarium does not prevent 

 certification. So certification of seed will not necessarily mean that 

 the seed need not be treated, but it will mean much more than that. 

 It will mean that the variety is pure, and that the inherent tendency 

 to bear a big crop as well as a good crop is present in the seed. St-ab, 

 Rhizoctonia and Fusarium, to a certain extent, can be controlled by 

 seed treatment, but no treatment can be given which will eliminate 

 a poor bearing tendency and a mixture of varieties, or a poor strain 

 of a variety. Hence, the important thing is not. after all. to be able 

 to secure seed that is absolutely free from controllable diseases, but 

 to be able to secure seed that possesses vitality and purity. The 

 presence of these qualities can be determined only in the field while 

 the potatoes are growing and when they are being dug, and not when 

 sacked or stored in the cellar after cligging. The care with which 

 certified seed is inspected and handled by a state inspector, should 

 exempt it from further inspection in the counties, and. again, the 

 co-o])erati()n of the countv horticultural commissioners is solicited. — 

 G. P. W. 



Mottle-Leaf.— "Mottle-leaf of Citrus Trees in Relation to Soil 

 Conditions" is the title of an article by Lyman J. Briggs. C. A. Jensen 

 and J. W. :\IcLane, of the United States Department of Agriculture, 

 appearing in the Journal of Agricultural Research, Vol. VI, Xo. 19. 

 This article is summarized as follows: 



"Mottle-leaf of citrus trees is characterized by the disapiiearaiice of chlorophyll 

 fniiii parts of the leaf. I lie purl ions fjirtliest removed from tiie niidrih aiui larger 

 veins heiiisr tirst affected. As the disturliaiue progresses, the ytdlowish spots increase 

 in size until the only remaiuing- chloroi)hyll is confined to narrow areas along the 

 midrib and the larger veins. The advanced stages are accompanied by a marked 

 decrease in the size, quality, and yield of fruit. No organism has yet been proved 

 to be casually associated with mottle-leaf, but the citrus-root nematode has been 

 found by Thomas to be widely distributed in mottled districts. 



Mottle-leaf is found in most citrus fruit sections of California, but is more 

 prevalent in some districts than in others. All the citrus fruits grown in California 



