So much to learn 🙂

Taking kids around the Royal Botanic Garden Sydney can offer so many learning opportunities!
This week we completed another round of kids holiday science programs at the Maiden Theatre in the gardens and we couldn’t help but incorporate a guided walk as part of the biology workshop we were running. So, with camera in-hand we took photos and discussed a number of things with the kids about the science all around them. It’s such a fantastic open space in the heart of Sydney, we reckon you’d love to find out more about this place too!

Native stingless bee colony

Native stingless bee colony in a tree stump

Just outside of the Maiden Theatre in the garden you can find a stump with a native stingless bee hive (look to the left of the path as you walk toward to the palm house). These little black bees, Tetragonula carbonaria, are one of over 1600 native bee species known in Australia. The hive contains over 10,000 bees which you can see become active once the day temperature rises above 18 degrees Celsius. If you look closely at the bees you’ll notice pollen stuck to their legs, some of which can be different colours depending on what plant the different bees were visiting. Try to watch their flight path; these bees can travel up to 500 meters to a food source. The kids in the holiday science program loved checking these bees out!

Native stingless bee – photo courtesy of Australian Museum

Classroom experiment: Make an insect pooter

The cactus garden

Cacti fascinates kids and there is quite a bit of biology you can cover as you walk around the cactus garden (just adjacent to the Maiden Theatre). During the plants for life workshop we ran at the garden we were able to discuss a variety of cactus concepts with the kids;

• Water conservation is very well demonstrated in a cactus. Cactus are succulent in that they hold water in their stems and leaves like a reservoir. Much of the cactus is covered in a waxy cuticle to prevent water loss. A cactus also has a shallow root system which can spread over a meter away from the plant, allowing the cactus to access any water in the soil (these roots break away from the cactus during dry periods to stop water leaching back into the soil). Whilst the presence of thorns to deter herbivores from eating them, the thorns also serve another purpose in that they aid some cactus in water collection from the air by acting as surfaces for the morning dew to accumulate. All of these features allow cacti to survive in harsh semi-arid and desert regions.

  
  Cactus growing in Royal Botanic Garden Sydney

• You can talk about biological control of prickly pear (Opuntia stricta) in Australia, whereby scientists released the Cactoblastis moth (Cactoblastis cactorum) to combat the rapid spread of prickly pear in the 1920’s. North-eastern Australia was at risk of farming land and nature reserves being overtaken by the growth of dense stands of prickly pear and it was the larvae of the Cactoblastis moth eating the seed pods and leaves of this cactus that controlled the outbreak.

  
  Prickly pear cactus in Royal Botanic Garden Sydney

• Cactus plants are easy to propagate, whereby you can simply cut 10cm of plant stem, place it into compost, water and watch the cactus take root and grow over a period of a month or so!
• Pollination of cactus can be from birds, insects and even bats depending on the particular species. get kids to compare the different cactus flowers across the garden.
• You can discuss how fermentation of the sugars in Agave cactus can produce alcohol, namely tequila. If handled well you can discuss the importance of alcohol, including its use as an antiseptic, a cleaning product, some glues, as a fuel in some stoves as well as in petroleum, a solvent in chemistry, as a preservative for biological specimens… it doesn’t just have to be about drinking!

  
  Agave in the Royal Botanic Garden Sydney

Classroom experiment: Make a STEM garden

Learning about greenhouses

Palm house in Royal Botanic Garden Sydney

The oldest glasshouse in NSW can be found in the Royal Botanic Garden Sydney. The Palm House was built in 1876 and is now used as a function centre. Glasshouses work by helping to trap heat from the sun inside the glasshouse whilst allowing sunlight to pass through the window panes. As it is a closed system from the surrounding environment gardeners cannot only regulate heat and light for plants but also the air humidity as well as control pollination plus protect plants from strong winds.

Glasshouses, also known as greenhouses, are used by us during our Earth, Sun & Moon workshop as a metaphor for describing how heat from the Sun is partially retained by our atmosphere, which allows the Earth to have reasonably stable temperatures from day to night as it rotates compared to other planets. We take this analogy further in our Renewable Energy workshop to discuss how increased levels of carbon dioxide, methane and other atmospheric gases likely to be contributing to the enhanced greenhouse effect, whereby additional heat from the Sun is retained by these extra gases and are contributing to measurable climate change.

Classroom experiment idea: Make a ‘beanhouse’

Bromeliads – plants with their own water tank

Bromeliad – see the water at the top of the plant?

There is quite a large variety of bromeliads on show across the garden. Bromeliads are interesting in that many of them have what is known as phytotelmata (plant pools) in the centre of the stems. Apart from being a water reservoir for the plant, these little water ponds serve as habitats for fly larvae and other small insects. some bromeliad species have taken advantage of this structure to also become carnivorous too.

Golden orb spiders – nature’s master weavers

Golden orb spider up close

if you walk around the garden for even a short length of time you’ll quickly see spider webs. Many of these webs have been made by the common Sydney Golden Orb Spider, Nephila plumipes. Golden orb spiders are master weavers in that they build large orb-shaped webs. These webs are strong enough to catch large insects and in some recorded cases even microbats or small birds! Some kids expressed some concerns over having spiders in the garden which allowed us an opportunity to describe how these spiders help to control unwanted insect populations such as flies and mosquitoes, plus we talk about how not all spiders are venomous (many people confuse this with being ‘poisonous’ which actually refers to lifeforms that are toxic to touch or eat). Whilst showing kids the webs you can let them know that golden orb spiders vibrate their webs to distract predators such as birds and even some species of wasp. As always, when showing spiders to children you need to highlight safety … i.e don’t touch them! Unless you’ve received significant training to identify the species you’re handling it’s not worth the risk of being bitten.

Dinosaur plants!

There are some plants that have a very, very long history in the fossil record and you can find these in the garden as well. We’ll definitely include these as part of a future dinosaur workshop in the gardens during another school holidays!

• Cycads

  
  Cycads

Around the garden, you can find cycads, a plant group that has been found in the fossil record for over 280 million years and were very abundant during the Jurassic Period between 201 – 145 million years ago. Despite over 250 species known across the world, more than half of them are threatened with extinction in the wild. Cycads live in symbiosis with cyanobacteria which help fix atmospheric nitrogen for use by the plant (these bacteria also produce the strong neurotoxins found in many cycads too). A great chance to as a prompt for discussing symbiotic relationships found in nature!

• The Wollemi Pine

  
  Wollemi pine at Royal Botanic Garden Sydney

This pine was only known in fossil records until the discovery of a small stand of less than 100 adult trees in the Wollemi National Park by David Noble in 1994. Now known as Wollemia nobils, the Australian Botanic Garden in Mt Annan was able to successfully propagate the plants and they can now be found in plant nurseries across Australia. They are susceptible to a plant fungus called Phytophera spp. and as such the original stand of trees in the Wollemi National park remains a secret to the public to avoid visitation causing a rapid spread of the fungus from people’s untreated shoes. The Wollemi Pine can grow to 25 – 40 meters and it will be interesting to see how tall the grow in the garden.

Classroom experiment: Create a plant collection

Habitat for animals

The Royal Botanic Garden Sydney offers many habitat areas for animals. As you stroll around the garden keep an eye out for birds, bats, possums and more amongst the trees and pond near the cafe. This can prompt a discussion on the importance of tree hollows for arboreal animals or how the wetland is vital nurseries areas. Try using a science app to identify the animals you see or hear!

Cockatoos near a tree hollow

Lillies just near the cafe at the Royal Botanic Garden Sydney

Sandstone erosion

Sandstone erosion is evident across the garden (see the layers?)

It doesn’t just have to be about plants. A visit to the garden can offer the opportunity to show the underlying sandstone outcrops that typify the Sydney CBD. Erosion is a natural process of wind and water gradually breaking down rock over time. As you show the kids the eroded sandstone be sure to show them the layers that are within the rock that was created as sand was deposited over millions of years to form the rock. Given some context during our Geology Rocks workshop, the kids enjoyed trying to find the sedimentary rocks around the garden!

Classroom experiments: Build a simple erosion model or Create a Cave

Bamboo

Bamboo

Bamboo is worlds tallest grass and you can find stands of different varieties across the garden. Look amongst the bases of the stems to show that bamboo spreads using interconnected horizontal stems called rhizomes. Rising from the rhizomes are the individual stems called culms. Bamboo is the fastest growing plant on Earth, growing nearly a meter in 24 hours in the perfect climatic and soil conditions (just beating kelp which can grow at just over 0.5 a meter a day in). Bamboo is incredibly strong and as such is used as scaffolding in some Asian countries.

Learn about the structure of flowers

Hibiscus flower

A trip to the gardens is a perfect chance to learn about the structure of flowers. It can be handy to bring along a hand magnifier to examine the flowers to find where the pollen is plus the arrangement of anthers, petals, sepals and more. Your smartphone can be handy as a magnifier by taking and enlarging photos too!

Variety of flower types

Learn about the variety of leaves

Variation in leaves between plant species

Leaves themselves can be incredibly different depending on what the type of plant you’re dealing with. Is the leaf broad? Is it darkly coloured or light? Is it spiky or flat? Are there hairs? The variations of leaves can help plants survive cold or hot climates, light or dark conditions, predation or lack of water. As you take the kids through the garden point out the differences you see and ask kids to explain the reason for their structure.

Classroom activity: teach plant structure by raiding your fridge!

School science visit on plants

As you can see, there is so much to learn about when you’re touring a botanic garden. Whilst it can be tempting to rush along the paths to get to the main attractions there are still great things to learn along the way. If you’re preparing your class or family for an educational trip to the garden perhaps you could create a simple checklist of things to look for and photograph (points for the rare things!). This will help them know what to look for and help keep structure to your outdoor lesson. Either way, taking kids outdoors is a great thing and is certainly something to be encouraged!

Happy teaching,

Ben Newsome.

Explore plants further with our ‘Plants for Life’ workshop!

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