-5- 



Since X-Disoasc seems always to bo associated with diseased choko 

 cherries, it is un-.;ise to plant a peach orchard anj'T/here near these alternate 

 host plants. And i/henevor diseased trees shov; up in the orchard it is v/ell 

 to ro2Tionbcr 'that X-Diseaso is incurable and that the fruit is certain to be 

 bitter • and lonsalablc. In a poach orcliard as in ojiy other kind of an orchard, 

 diaf^noBis is of utmost inportance, for only than can proper stops be taken 

 to insure healthy, hi^h producing trees. 



MGIJESimi DEFICIEi^JCr , A MJOR PROBLEM 



Many of cur soil t;.'pcs alonp- the Atlojitic seaboard are notoriously 

 low in the olcnent rnagnosiun. Crop removal, erosion and leaching tend to 

 deplete the already liirdted supply of this highly essential elonont. It is 

 well to bea.r in rdnd that maj_;nasiun enters into the composition of chloro- 

 phyll, the green coloring matter in plants, TJithout an ample supply of mag- 

 nesium, no green plant, that is no plant dependent upon the products of 

 photosynthesis, can function normally. Distinct sj^'mptoms of nagnesiuia do- 

 ficioncy have bocn observed in the follo'ving fruits in Massachusetts, - 

 apples, poaches, grapes and raspberries. The most coinmon syiaptoms are a 

 yellov.dng or brov.-ning of certain parts of the leaf blade between tho veins. 

 The midrib and veins tend to remain green while other parts of the leaf take 

 on a yellowish or brovmish color. Early dropping of Mcintosh apples is another 

 symptom, of magnesium deficiency* 



As much lime has probably boon applied in Massachusetts orchards 

 during the past 5 years as was applied during the previous 10 years. But 

 only a start has been made in replenishing the r.agnesiura by this means, and 

 in many cases the soil is still extroruoly acid as a result of repeated ■appli- 

 cations of svilfur over a period of years. It should bo the goal of evcs^r 

 orchardist to apply enough high magnesium lime to bring tho pH up to at least 

 5,5, This conditioning program ■'vill not only replenish the supply of m.ag- 

 nesium and calcium, but at the same time it will h.clp to make available other 

 elements including nitrogen, Tho cover crop v;ill tend to improve as this 

 balanced condition is restored and greater benefits will be obtained from a 

 comploto fertilizer application since there will be less tendency/ for mineral 

 elements to remain in an \;inavailable form. 



Such a progrrun may be considered as a form of insurance against a 

 mxagnosium deficiency, 5, 10, or more years ahead. But high magnesium lime 

 cannot bo relied upon to provide needed magnosiujTi in the tree this year or 

 next. It is too slovr acting to provide nsedod roagnesiuni promptly, I'/here 

 deficiency symptoms exist, Epsom salts, knov.-n to tho chemist as magnesium 

 sulphate, is one of the recommended materials, 3ot;i high magnesium lime 

 and Epsom salts should be used in a vcrj^ acid- soil v;hcre there is reason to 

 believe that tho supply of available magnesium is at a low level, A high 

 magnosiijm lime will servo a verj/- useful purpose in future years while the 

 Epsom salts v;ill tend to supply needed magnesium within a fev: months. 



