Timing of Spring trip to Sequoia NP

Thanks to all for your responses. While we would like to stay in the park we knew that would not be likely. We had to make our reservations in the Tetons two years ago many months in advance. With the possibility of snow at any time it may be best to stay outside of the parks anyway. My question is if there is snow in Sequoia NP can you still get up close to the Sequoia trees without hiking in. I understand the idea of snow shoes which would be a lot of fun but my wife had both knees replaced and that is not an option. As far as Lassen NP goes it sounds like we will need to check conditions before we head that way. As far as Yosemite goes we will definitely stay somewhere like Mariposa as that is what we did when we went by car many years ago. Thanks again for your input.