“Many of the early settlers in our province gathered oyster shells at low tide from some of the many extensive deposits that occur in the bays and rivers throughout ‘The Island.’ They burned these shells to secure quick lime, required in making the mortar, which they used in building their chimneys and fire places ,and for plastering their houses. They also observed that where these shells were burned the vegetation in the years following, was much more vigorous, this was particularly true of clover, cereals, and some of the vegetables.

“The top layers of many of these deposits, particularly those that were exposed at low tide, were composed largely of blue mussel shells in various stages of decomposition. Ingenious farmers invented and constructed mud-diggers of different types, but quite efficient for the lifting of these deposits. Some of the first ones were mounted on scows, but it soon became a general practice to lift mud through the ice in winter. Most of the surface deposits of mussel mud were quickly exhausted.

“Underneath these there were usually deep deposits of oyster shells, sometimes almost pure oyster shell mud was located that extended to a depth of more than twenty feet. These muds were all referred to as “mussel-mud” the name carried from the surface deposits that were first used on land. It was a common sight, early in this century, to see dozens of mud diggers on many of our rivers and bays in winter. We have seen maps prepared for the Provincial Government, showing oyster beds in Malpeque Bay that extended over a hundred acres each. On some of these beds there are deposits of oyster shells over ten, fifteen and twenty feet. 

VALUE OF SHELL-MUD

“The first application of shell mud to land not previously mudded was very beneficial. It invariably produced luxuriant crops of clover, (we remember fields that did not need to be raked, as large coils were not more than twenty feet apart), followed by increased crops of roots and grain. These muds were essentially lime, most of them contained eighty-five per cent and over of carbonate of lime with traces of nitrogen and phosphoric acid. They were good soil amendments. The farms near some of these deposits received very heavy dressings in the early days, but second applications proved of little value. The growing of certified seed potatoes was partly responsible for the decline in the use of oyster shell mud, which tended to increase potato scab. 

“The mud was either piled on the shore or near a highway where it could be hauled away later or piled in small heaps on the fields and exposed to frost, which broke down many of the shells before being spread on the land. We recall buying good shell mud at the diggers at four to six cents per scoopful of from 400 to 500 pounds. 

“The railway ran a spur line to a pier on St. Peters Bay near large shell deposits. The price charged for a 12 1/2 ton car (enough for an acre) of mud was $3.50 for many years. In 1920 this had been raised to $14.00 F.O.B. point of shipping. The value of lime for Island soils being established as a valuable soil amendment, ground limestone from the mainland has been imported in increasing quantities.” 

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