Tagasaste (tree lucerne): Friend or Foe?

Tagasaste or tree lucerne (Cytisus proliferus), is a small evergreen tree that grows 3-6m high (depending on soil and rain) and is a popular plant for people looking to regenerate poor soils and feed livestock.  It’s indigenous to the dry volcanic slopes of the Canary Islands and was introduced to Australia some time around 1879 when seeds where sent from the Royal Botanic Gardens, Kew, England to the Adelaide Botanic Gardens.

Image from Pastures Australia

It has a varied reputation across Australia. While some farmers and land holders love it and swear by it for its incredible ability to grow in the shittiest of shittiest soils and provide nutritious fodder for their livestock – others dedicate their lives to removing what can become an invasive species if left unmanaged. So if you’re looking to start a lively conversation with folks who only want natives in Australia, this plant will deliver just that.

Permaculture has some baggage around spreading weeds. I’ve heard people say things like “permaculture is nothing but a strategy to spread weeds” and “permaculture gardeners are messy, they’re just propagating invasive species and they’re so lazy they let them get out of control.”

I’m sure sometimes this has been true. But I bet $5 (I’m not loaded) that when it comes to spreading invasive plants, I reckon ornamental gardeners have more to answer to than permaculture gardeners. I write this as I look out across a hillside of “native” bush which has thick understory of cotoneaster. A local who’s lived here since the 1960s told me that after the devastating 1967 fires that literally burnt most of Hobart, cotoneaster was one of the few plants that thrived in a burnt landscape, so ornamental gardeners planted it. Fast forward to now and it has firmly integrated itself into our whole peri-urban bushland – it’s become naturalised. I should know, as every day I harvest large branches of it for our goats. That and hawthorn – the other ornamental weed that’s making itself at home in local bushlands.

But this is not a blog about who’s a worse gardener or land holder. It’s a little dive into our relationship with plants and how we respond to the inevitable traveling of plants from one continent to another and the naturalisation that occurs after plants exist for decades, thriving in particular climates and soils.

I sit on the fence with this one. We live in urban Hobart where plants such as ornamental weeds including cotoneaster, willow, ivy, privet, and mirror bush (to name a few) are fostered in private gardens. As small-town-Hobart is also tightly hugged by bush, there are also a range of “environmental weeds” such as gorse, tagasaste and boneseed that *pop up everywhere*. I do believe that to remove all these weeds is impossible now. Their seeds are in the soil waiting for the right conditions to grow. Most, if not all – have naturalised, meaning they’re here to stay and now it’s up to us in how we respond to them.

Before we go any further, let me be very clear that I do not advocate actively introducing ornamental or environmental weeds into areas that don’t have them. For example properties neighbouring national parks, wild grasslands, pristine coastlines or vibrant water ways should be protected and maintained for the precious, unique ecosystems that they are. For these places, the Department of Primary Industries, Parks, Water and Environment (DPIPWE)  promote planting native “tagasaste alternatives” to get a similar function, specifically Prickly box (Bursaria spinosa) and hop bush (Dodonaea viscosa) in dry areas and local Tasmanian native acacias for high rainfall areas.

But for urban and peri-urban areas where weeds are naturalised, wouldn’t it be interesting to look at how we can co-exist and evolve side and side? Again, I’m dead keen on maintaining native biodiversity *everywhere*. I’m just not keen on spending the rest of my life poisoning weedy plants in the name of native is best and everything else must die. 

So what do we do in our own garden? Tagasaste has popped up everywhere. We pulled out most the baby trees as we don’t need 1000 of them. However, we saved around 10 and interplanted them between our fruit and nut trees to act as nurse trees for the next 5-10 years or so. Nurse tree functions vary, in this case the tagasaste is fixing nitrogen into the soil (improving its health) and growing more quickly than the fruit and nut trees – therefore providing eventual wind protection (we have gnarly winds). As a major side bonus, they’re already providing fodder for our goats who love the fresh branches and leaves. You can see its nutritional benefits for livestock outlined below.

Comparison of tagasaste foliage with other common stock feeds

Chart from Permaculture Plants, Jeff Nugent & Juilia Boniface – sorry about the bad scan. 

Let it be know this is the only “environmental weed” we’ve actively fostered on our property. I’m always pulling out baby boneseed and gorse. We happen to have inherited an old windbreak made up on cotoneasta and pittosporum which we’ve chosen to keep due to those gnarly winds I mentioned above. Other than this, we plant only natives and fruit/nut trees and diverse shrubs.

So is tagasaste a friend or foe? I love and respect all plants and all unique ecosystems.  At the end of the day it comes down to your environmental and social context. In our case, tagasaste is a friend, but a bloody well managed one.

7 Responses to “Tagasaste (tree lucerne): Friend or Foe?”

  1. Jen

    I was wondering about the gorse and boneseed in our somewhat degraded bush out the back. I wonder if it is performing some environmental function or remediation of degraded soils, seeing wallabies don’t eat it and they have overgrazed most of the other less prickly understory plants. I was on a mission to kill it one plant at a time a while back, with a long term view of pulling out seedlings until the soil seed bank was exhausted. but now I don’t have the energy so it lives on, producing more long lived seeds every year… but perhaps providing useful understory, soil stabilization, protected habitat for critters, tree nursery functions… ?

    Reply
    • Jenn

      I don’t know about bone seed, but gorse absolutely performs a function. Here, it grows in degraded and disturbed soils, fixes nitrogen, and prepares the soils for what comes next. Eventually (i.e., if humans would leave things be), it will be succeeded and shaded out, pushed to the sunny margins. Someday folks may figure it out. Until then, they’ll keep ripping out forests and complaining about gorse. 😁🌱

      Reply
      • Hannah Moloney

        Yes, true Jen – gorse does provide some functions. We just don’t want it here as it’s so prickly and our goats don’t eat it as they prefer other fodder. They would if they had nothing else to eat though!

        Reply
  2. Jenn

    Sounds like it depends as who you ask! I’m wondering about cotoneaster. We’ve got it too Southern Oregon Coast, USA)…everywhere. The sheep appear to love it, but upon further research, it appears that all parts of the plants are toxic (???). I discovered this while researching whether or not to give the sheep cotoneaster with berries. They haven’t seemed unhealthy after eating it, but I’ve only given it to them without berries. What’s your experience been?

    Happy growing!
    Jenn (@wildrootspermaculture)

    Reply
    • Hannah Moloney

      Ah yes, our goats eat it every day, love it and are wonderfully healthy. When it has berries, they eat around them – likewise with hawthorn (the berries are apparently poisoness). Also, when we grass them on grass as there’s hemlock growing amongst it, they eat around it. Animals are clever!

      Reply
  3. Cathie Turnbull

    Some are not that clever and you should NOT give them access to poisonous plants, especially young animals. Introduced plants get rid of and plant what is natural to your area for achieving what you need. Gorse should never have come to nz as it does compete with natives, it thrives in our climate. In England it is manageable
    here it is not so for the sake of everyone that lives anywhere near you remove it. Tree lucerne is great but needs management near native plantings.

    Reply

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