Native of the High Steppes Close your
eyes and let's go back nearly two thousand years. The earliest tulips
grew wild then — without any help from humans. They were native
to the high steppes (grasslands) and mountains of Asia.
Their annual life cycle today reflects how they survived conditions where
they developed thousands of years ago. Imagine you
are a bulb of one of those tulip plants. The summers are very hot and
dry and the winters are harsh and cold. How might you survive? What challenges
would you face?
Where Did I Come From?
The map shows
where in the world you came from. You are buried at 46 degrees north latitude.
Draw an imaginary line across the map. Which states or provinces share
the same latitude? You are in the mountains. It can get to 40 degrees below zero there.
Most of the water is frozen.
Adapting to the Climate
What would
happen if you came out of the ground during the winter? Plants that did
that didn't live. Your ancestors survived because they poked
out when conditions were right. Now you naturally do the same.
In fact, you need at least two months of cold underground temperatures
before you'll pop out of the ground.
Surviving Spring Snows
Spring is coming. The days are longer each day. The sun
feels stronger, too. The snow melts and trickles down to your roots. You
push your leaves up out of the soil. It may snow
again but your leaves can survive it. (After all, your ancestors developed
in this climate.) The bud that will become your flower grows more slowly.
Can you find the bud? How do you protect it?
Physical Adaptations
Look closely
at the leaves. What do you notice that might help you survive the coming
hot, dry summer? Your leaves
have a waxy coating. This keeps them from losing water from inside. It
also protects them from "sunburn" and diseases. What do you
notice about the shape of the leaves? How might they help you get what
you need to survive? Insects are
attracted to the color and sweet nectar of your flower. As they touch
the dusty pollen, they bring it to new flowers without even knowing it.
This helps you make seeds. It takes 4 to 7 years to go from a seed to
a flowering size bulb!
Underground Package
As summer
nears, it is getting hotter and drier. How will you survive? First your
flower dies back. There isn't much water available, so your roots dry
up. Your outer skin gets tough. Without any water, your leaves can't make
food, so they die back, too. But before they do, they send the rest of
the food energy they made down to an underground bulb — and to new
baby bulbs (bulblets).Now here
you are: a little underground package ready to rest (go dormant)
until you have what you need to grow. Good thing too, because winter is
coming!
Activity Underground
In the fall,
the soil gets colder. People think you are resting underground.
But something new is happening . . . slowly. If we dug you up, here's
what we'd see. You have
been through this cycle before. You naturally use your stored energy (and
some moisture in the soil) to start growing roots again. After all, spring
would come once more. This is how you spend the winter.
The Cycle Continues
As water and
warmth return in the spring, you use the rest of your energy to push leaves
up out of the soil. Your flower bud follows . . . and the cycle begins all
over! |