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Show I j HORTICULTURE H Tliis Department if Edited by Prof. ,R S. Northrop Sute Ajri- r . cultural College. I ORANGE RUST OF BLACK BERRY. i'rof.fjS. H. Favor, U? A. c! ' 3t . " j h a ncre jpiareSentfyccir. reported from, this state an outbreak of a dis- ois known as the orange rust of blackberry. It is very doubtful if this H is the fir.st appearance of this disease, H but on 'account of its presence it is -of H importance for the fruit growers, and H particularly the blackberry growers to H be on the lookout for it. H TltisMiscasc is caused by a fungus, H va minute plant which' li?cs entirely H withiwtjic tissucsjof the blackbcrny 1 raB -'. H rlantrartd on account of this facKlhcv disease vcan gain igrcat? headway 'be-' forcibeing discovered. The fir,3t H symptoms of the disease is that the H youngMuincs or suckers of the black j bcrrvshow a tendency to grow very H slcndcrwjUi ft spificwhat unusual lcngUQgj$jjr JB& lSBUiMiSi course of time, usually late in the B spriiig or at about tho tjniQ the blacks H berry fruit is ripening, the under siilC of the loaves of these slender canes will be found rto bo covered with small irregular patches of a bright orangeor golden yellow dust. Sometimes Some-times these patches will be covered ', jyith a very thin skip, which later on breaks and allows the powder to cs-;capc. cs-;capc. This powder is madc up of the r spores orjncnfodiicticjbodics6f the fungus. These spores arc not; seeds but they serve the Lame purpose a seeds, in hat they can grow into a new plant under suitable conditions. A single sp'orc is so small that it if invisible to the naked eye, but nevertheless, never-theless, where one of these spores falls on a. leaf of a blackberry plant on which there is. a bit of dew ori! rigation water, 'it germinates1 and I i 'i '" penetrans the Jcaf of pthc blackberry. As 'soon as this funcus gels inside'lhe blackb'ctry leaf, its minute thread-like j body i enctrates here and there throughout the cane of the blackberry, black-berry, eventually getting down into the roots. And it is on account of the presence of this fungus in ' the rotsthc blacJIbcrnyhat Jhc- danger dan-ger comes. It can live thcnjfxpni .year; to ycar,k and grow -as the host grows, causing the reappearance ci'ch year of the sickly, slender canes, which will produce pro-duce masses of yellow spores on the underside of each leaf. On account of the nature of the fungus, plants winch arc once attacked attack-ed rarely recover, and any plant which shows the characteristic orange colored col-ored blisters or powdery masses should be dug up, loot and branch, and burned at once else it will serve as a breeding place of the parasite. Neither should joung plants be taken from plants known to be infested in-fested with the fungus as they will in all probability be infested with the fungus and isoon be killed by the disease. dis-ease. Young plants should be select' cd only from the strongest, most vigorous vig-orous and fruitful stools and from stools which show no signs of infection infec-tion with this1 orange lust fungus. Not only is the blackberry liable to attacks of this disease but the dewberry dew-berry as well is often affected. On the dewberry the orange rust presents the same characters as the blackberry and needs to be treated in the same manner. Raspberries arc free from this disease. Some varieties of blackberries are morc,liabJc to attack of orange, rusl, than arc others. The Early Harvcsr, Kittitinny and Ancient Britton being particularly susceptible, and especial- 1 ly so in a season of great rain fall, i as this lias been. Taylor is somewhat i susceptible, while Snyder and Knox 1 arc the least liable to the disease. I The means of control of this dis- 1 f case consists simply in the removal I of diseased plants. Spraying with I fungicides such as Bordeaux mlxtinc, will not cure an infected plant, but ic $ would serve in piotecting plants I against infection. There arc many j fungi which work upon our ciops, I causing diseases of various kinds, some of which are easily controlled i while others arc nor. The Depart- ment of Horticulture of the A'gricul- I tural College ait Logan, Utah, is in- s formed rbout these various plant dis- ij cases what they aic and how to con- jj trol them, and if the readers of this paper want information about' any disease affecting his crops he is re- quested to scud a simple of the dis- ! case affecting his crops with a letter ; i to the Department of Horticulture of the Utah Agricultural College. j |