MY EXPERIENCE This summer I flew out to visit family in Palm Springs, California. While I was in California my aunt and uncle took us sight-seeing to many different places. One of the most interesting places they took us was to see the Joshua Trees in the Mojave Desert (approximately an hour out of Palm Springs). We took a drive through the Joshua Tree National Park and it was an amazing sight and experience!
QUESTIONS Where are Joshua trees found? What are some characteristics of Joshua trees? What does the weather need to be like for these trees to grow? What is the history of these trees? What are some interesting facts about Joshua trees?
Connections with Standards
4th Grade Standard: 4.4.3 – Observe and describe that organisms interact with one another in various ways, such as providing food, pollination and seed dispersal.
*Talk about the pollination process of the moth and Joshua trees.
5th Grade Standard: 5.4.4 – Explain that in any particular environment, some kinds of plants and animals survive well, some do not survive as well, and some cannot survive at all.
*Talk about the climate in the Mojave Desert, how Joshua trees only grow in this type of climate and how other plants could not survive this weather.
Where can you find Joshua trees? Joshua trees grow best at elevations between 2,000 and 6,000 feet. They also prefer flat or gently sloping terrain, and are usually supplanted on steep hills within their range by blackbrush and other scrubs. Joshua trees are ONLY found in areas of southwestern California, Nevada, Utah, and Arizona. Taken from: http://www.livingdesert.org/plants/joshua_tree.asp
Characteristics of Joshua Trees
Scientific Name: Yucca Brevifolia
Giant member of the Lily family
Joshua trees have relatively short leaf blades and the bark is rough and grayish brown. Also have flower blooms during the months of February to late March
It blooms from the terminal points of the stems and the flowers are arranged densely in the panicle or compound flower structure.
Like all desert blooms, Joshua trees depend on just the perfect conditions: well-timed rains, and for the Joshua tree, a crisp winter freeze.
Some of their branches extend to 30 feet.
The Joshua tree has a special relationship with its pollinator, the yucca moth.
Taken from: http://www.livingdesert.org/plants/joshua_tree.asp
Climate in the Mojave Desert
Days in the Mojave desert are typically clear with less than 25 percent humidity.
Temperatures are most comfortable in the spring and fall, with an average high/low of 85 and 50°F (29 and 10°C) respectively.
Winter brings cooler days, around 60°F (15°C), and freezing nights.
It occasionally snows at higher elevations. Summers are hot, over 100°F (38°C) during the day and not cooling much below 85°F (29°C) until the early hours of the morning.
Taken from: http://www.nps.gov/jotr/index.htm
History of the Trees It is said that Mormon pioneers named the species Joshua trees for the biblical figure Joshua, because the trees uplifted limbs reminded them of Joshua praying and pointing to the heavens. The Joshua tree was also recognized by American Indians for its useful properties: tough leaves were worked into baskets and sandals, and flower buds and raw or roasted seeds made a healthy addition to the diet. Taken from: http://www.nps.gov/archive/moja/mojaanjt.htm
Interesting Joshua Tree Facts
The tallest Joshua tree in the park looms a whopping forty feet high, a grand presence in the Queen Valley forest; it is estimated to be about 300 years old!
These “trees” do not have growth rings like you would find in an oak or pine. This makes aging difficult, but you can divide the height of a Joshua tree by the average annual growth of one-half inch to get a rough estimate.
These trees are an important part of the Mojave Desert ecosystem, providing habitat for numerous birds, mammals, insects, and lizards.
Joshua trees have such a wide range of shapes, with bent and contorted branches, that it seems no two plants are alike.
It is hard to watch an hour of television without seeing a Joshua tree. Many commercials, movies, photo shoots are done in the land of the Joshua trees because of its beauty.
Taken from: all websites on resource page
The Loraxby dr. SEUss The artwork that Dr. Seuss does in the book, The Lorax, resembles Joshua trees. If you look at the pictures of his trees, you can see how he depicts similarities of the Joshua tree. This book is about the Once-ler describing the results of a local pollution problem. You could take the lesson in this book and turn it into another science lesson on pollution and the problems it causes. The reason I chose this book for a Joshua tree lesson is only because of the artwork.