Explanation
No. Most conifers are evergreen, but some are deciduous: they lose their needles in autumn and grow new ones in spring. Larches, dawn redwoods and bald cypresses are examples.
Harvard University's Arnold Arboretum identifies these deciduous conifers in its collection. University of Minnesota Extension independently describes tamarack, a type of larch, whose needles turn yellow and fall each autumn.
The terms describe different characteristics. Conifers are a group of cone-bearing plants, while evergreen describes foliage that remains present through the year. A conifer can therefore be deciduous, and seasonal needle loss is normal for those species.
Key takeaway
Conifer and evergreen are not synonyms. Some conifers naturally lose their needles each autumn.