Your dream presents several vivid and symbolic elements that can be interpreted in various ways. Let's break down the key components:

1. Driving in Traffic with a Fallen Tree: Driving often symbolizes your journey in life. The fallen tree blocking the road can represent obstacles or challenges you feel are hindering your progress. The fact that it was a large tree suggests that this obstacle is significant and perhaps overwhelming. The lack of backups on the freeway could indicate that you feel there are larger issues at play in your life that others may not be addressing.
2. People Stopping to Look: The curiosity of others stopping to observe the fallen tree might reflect your feelings about how others react to your challenges. It could be a sign that you feel your struggles are being scrutinized or that you are longing for others to understand your situation more deeply.
3. The Maintenance Men: The scene with maintenance workers cleaning the tree suggests a desire for order and beauty in your life. This could mean you are seeking to restore balance or clarity amid chaos. The act of taking pride in maintaining the trees might indicate a wish to care for and nurture aspects of your life or to acknowledge the importance of taking care of your environment and relationships.
4. Walking to a Birthday Party: Birthdays often symbolize reflection on life, growth, and change. The fact that you think the person being celebrated is dead introduces themes of loss and remembrance. This might indicate that you are processing grief or reflecting on memories of loved ones, particularly those who have passed.
5. Following a Woman and Reading Cards: This part of your dream suggests a connection to the past and a desire to honor those who have influenced your life. The act of reading birthday cards could symbolize nostalgia and a longing for the past, particularly for cherished memories with the deceased relative.

Overall, your dream seems to explore themes of obstacles in your life, the importance of maintaining order, and a processing of grief and memory. It may be beneficial to reflect on what obstacles you currently face and think of ways to address them, while also honoring the memories of those you have lost and integrating those memories into your life moving forward.