Such devices typically shoot off blue or pink smoke to signal the gender of an expected child.
The El Dorado fire near Yucaipa has burned more than 3,000 acres and forced evacuations in some communities.
“Cal Fire reminds the public that with the dry conditions and critical fire weather, it doesn’t take much to start a wildfire,” the California Department of Forestry and Fire Protection said in a statement.
It was one of several massive fires burning in California amid an epic heat wave.
A fire in the Japatul Valley southeast of Alpine has burned more than 9,850 acres and destroyed at least 11 structures in addition to 25 outbuildings.
The blaze, dubbed the Valley fire, was the nightmare scenario many had feared: a roaring wildfire chewing through vast stretches of the back country amid searing record-high temperatures, forcing homeowners to flee — all during a time of coronavirus-induced mask wearing and social distancing.
Boiling clouds of smoke pouring from the fire rose into the air and filtered over the county with an acrid stench, making for unhealthy air conditions.
The Bobcat fire in the Angeles National Forest near Duarte broke out Sunday afternoon and forced Labor Day weekend visitors to flee. It was not threatening homes.
In the Sierra National Forest northeast of Fresno, the 45,500-acre Creek fire trapped more than 200 hikers in the Mammoth Pool recreation area when it crossed the San Joaquin River on Saturday afternoon, prompting a massive rescue effort by the California National Guard.
The San Diego Union-Tribune contributed to this report.