RE-INVIGORATING OLD BEDS.

There is a wide-spread impression among horticulturists that worn out beds which have ceased to bear may, by means of watering and certain stimulants and warming up again, be so re-invigorated as to start into full bearing, and yield a second and a good crop. I have given this question much painstaking and practical consideration, and have absolutely failed to revive a "dead" bed. I have not been able to do it myself, and any instance of its having been done has never come under my observation. This may appear heresy anent the multitudinous writings to the contrary.

A mushroom bed may keep on bearing in a desultory way for many months, and now and again show spurts of increased fertility; but this is no second crop; it is merely a prolonged dribbling of the first crop. A bed, by reason of cold or dryness, may, as it were, stand still or partially stop bearing, and soon after it is remoistened, warmed, and otherwise submitted to congenial conditions, will display renewed energy; but this is no second crop; it is merely a spurt of the first crop caused by extra favorable cultural conditions. But to show how vaguely this question which is so much written about is regarded, let me quote from a letter to me by Mr. J. Barter, who grows 21,000 lbs of mushrooms a year for the London market: "You ask me, 'Do you ever get a second crop?' My beds last in bearing, on an average, each three months, and that I reckon to be three crops. But whether it be three or six months, the weight of mushrooms is about the same. As there is in, say a ton of manure, only so much mushroom-producing power, if you force it to produce that weight in two months you are a gainer, as you thereby save in labor; but when that producing-power is exhausted it will produce no more mushrooms."

A spent mushroom bed is one that has been kept in bearing condition under the most favorable circumstances at our command, and it has borne a good crop, lasted some two months in bearing, and now it has stopped bearing (except in a meagerly, desultory way) because the spawn or mycelium has exhausted itself and is dead. Then, without living spawn in the bed how are we to get mushrooms? Some bits of mycelium are still alive and yield the desultory few, but every mushroom that they yield is preying on their vitality, and after a time they too shall die and the bed be completely barren, for the mycelium is altogether dead, and without mycelium mushrooms are an impossibility. We can keep mushroom mycelium in active growth the year round, and year after year, providing we never let it bear mushrooms. This is done by taking the mycelium, just before it begins bearing, from one manure bed and plant it in another, and so on from bed to bed. At every fresh transplanting the mycelium exerts itself into renewed growth, for it must become a strong plant before it has strength enough to produce and support a mushroom. Our utmost efforts have never rendered mycelium in a mushroom-bearing condition perennial.