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Show POTATO SCAB. 8ome Suggestions for the Treatment of the Disease. Tho truo potato scab Is a skin disease dis-ease and dovclops from a germ. A plcturo of scabby Bced Is Bhown. There will bo no scab on tho crop unless theso germs nro either In tho soil when tho crop la planted or on the seed. Prevention thereforo depends upon two things. Wo should avoid planting In soil whero tho germs aro found. If this Is impossible wo should handlo tho soil so that tho germs will not bo actlvo. It seems to bo settled that sulphur acts to destroy tho germs. Somo potnto growers In places where Bcab Is bad put sulphur In tho hill or drill. 'When potnto planters arc used the sulphur is mixed in tho hopper and dropped with tho 3ecd into tho furrow. It helps destroy tho Bcab nnd prevents tho seed pieces from rotting, ospoclnlly in n damp season. Tho scab gorms dovolop best In nn alkaline soli. Lime, wood ashes and manure are all alkallno, and will usually caiiBo trouble when tho soil Is known to bo well supplied with tho germs. Whon n green crop is plowed under tho soli is soured moro or less, and this condition Is best for scabby ground or seed. Wo havo known farms " ' Scabby Potatoes. whero a five-year rotation Is followed to show somo curious results. Ono flold would show far moro scab than another and somo seasons seem to favor the growth of scab. On thoso farms potatoes follow corn, and wo think there Is less scab when crimson clover is seeded in tho corn and plowed undor In spring. This seems to show that tho theory nbout a sour soil is sound. Thoro nro thrco methods of treating tho seed dusting with sulphur, soaking soak-ing with somo chemical to destroy tho gorms, nnd fumigation. Tho dusting is easiest, but not always effective. Wo cut tho scod Into peach baskets and scatter three handfuls of sulphur over tho seed as It Is put In. Tho basket Is shaken down nt Intervals. As It stands on a pnpor tho sulphur which fnlls through can bo saved. For soaking formalin for-malin is now gonerally used. This liquid chemical, also called formnldo-hydo, formnldo-hydo, can bo bought at drug stores. Tho proportion Is ono pint of formalin to 30 gallons of water. It can bo put-In put-In a barrel or largo tank, depending on tho amount of seed to bo soaked. Wo uso two barrels, ono with tho soaking liquid and tho other containing contain-ing clear water. Tho potatoes nro first rinsed In tho wnter. Thoy aro put In a coarso sack and soused up and down In tho barrel. An easy way to do this Is to havo a pulloy fastoned ovor tho barrol so that tho bags can bo easily ralMsrt or lowered. After rinsing tho bag Is loworcd into tho solution and kept there two hours. Thpn tho potatoes pota-toes aro taken out, dried and cut. Tho rinsing takes off tho dust, thus making tho solution cleaner. Fnrmora havo different methods of doing this soaking. soak-ing. The principle Is to kcop tho seed In long enough to kill tho scab germs without hurting tho sprouts. Fumigation la now used by somo largo growor's, soya tho Uurnl Now Yorkor. At llrst experiments woro tried with sulphur fumes, ns thoy nro used for fumigating houses, hut this did not succeed. Now tho gas from formaldehydo Is usod with success. Instead In-stead of soaking the seed in a solution of this chemical it la turned Into a gas and hold In a close room with tho seed. Tho procosB is described aa follows: fol-lows: "For a gonorator a small galvanized washtub about 1G Inches In dlamotor at tho bottom was placod In tho centor of tho room about a foot from tho floor, midway between tho two llnoa of crates filled with potatoes. Whon ready to use 31 ouncos of potassium permanganate was spread evenly over the bottom ot tho tub, then four pints and ono ounce of -10 per cent, formal-dohydo formal-dohydo pourod ovor this. Tho tub was given ono rapid tilt to entirely wet tho potassium pormangandto with tho formalin and then tho door was quickly and tightly closed from without. Tho nlmost entire absence r' tho odor of escaping gas while tho itmont was In progress Indlcntod t '..' the room was practically airtight. Thb door remained closed for 2-1 houra, and when opened tho gas was still so strong that It was ImposBlblo to work In tho room for from 20 to 30 minutes. In fact, thrco weeks aftor the disinfection was finished a distinct dis-tinct odor of formaldehydo could bo detested In tho room. Tho scod for tho entire 20 acres was treated In thla way, care' being taken to placo tho treated seed In barrels which had novor boen used for potatoes bofore. This Is to avoid contamination In taking to tho flold after treatmont." |