The experience of Forget and Des Groseilliers had galvanized aspiring traders. No less than thirty joined the procession of canoes preparing to leave soon for the Pays d'en Haut. Unfortunately, upon reaching Trois-Rivières, they learned that the Iroquois had declared war again and were waiting ahead to ambush their convoy. The lure of profit was overcome by the fear of danger, and the young adventurers returned home.

The renewal of hostilities with the Iroquois Nations impeded the activities of the coureurs des bois. However, in the middle of the 1660s, about 3,000 soldiers and hired men arrived in the colony, following which there was an enormous increase in 'wood running'. In February 1668, the authorities of the colony observed that "a band of Natives without any French among them is a rare sight indeed". In July 1669, a new report reads: "Several individuals, soldiers, volunteers and settlers, have gone wood running to the Natives, as far as thirty, forty, even fifty leagues away".

Faced with a movement that seemed to be growing disproportionately, the authorities became anxious. In a memoir dated from January 1672, Jean-Baptiste Patoulet, secretary of Intendant Jean Talon, asked Minister Jean-Baptiste Colbert for the permission to intervene, emphasizing the fact that the colony could only count on a mere 3,000 to 4,000 men capable of bearing arms, while the coureurs des bois numbered 300 to 400. Patoulet also maintained that these individuals did not marry nor cultivate the land, they were infinitely disorderly in their conduct and that they were an obstacle to the conversion of the Natives.