And while she looks back at her early life largely through the lens of positivity, it was a devastating family tragedy that put the wheels in motion to send her to various countries around the world.

"I was born in Albury and grew up on a mixed sheep and wheat farm near Walla Walla," she said.

"We were there until I was about seven, and that's when my father took his life.

"Farmers do an incredibly important job in food production and environmental stewardship, but this can be very stressful. Communities and governments must support farmers in balancing all the risks of climate change, increasing costs, variable prices, etc, to achieve sustainable productivity."

It is a public health issue Prof Lemerle has also witnessed first-hand while working with rural communities in Australia and overseas.

"I think it's important to talk about these things because when I was a kid, they didn't," she said.

Prof Lemerle's life changed course, and she moved to Tasmania for a few years with her family before her mother remarried. The family moved to England for 10 years, where Prof Lemerle's interest in pasture and crop weed management was sparked, leading to a career in agricultural research and a life-long passion for agriculture and working with farmers.

"I was lucky we travelled when I was a kid, and also got a good education - I went to secondary school and university in the UK, where I studied agriculture," she said.

Prof Lemerle scored a job with the NSW Department of Agriculture (now NSW DPI) at Wagga in 1980, where she spent the first decade of her professional career focusing on herbicides.

"Herbicide use was starting to really take off in Australia, and we were looking at a lot of herbicide options, both pre and post-emergence herbicides for weeds in crops and pastures, which was my focus," she said.

"We spent a lot of effort improving the performance of herbicides and trying to minimise their environmental, animal and human health risks.

"I came for a three-year job, and I'm still here 44 years later; it's such a great place to live and work in a regional centre like Wagga Wagga."

At the same time, Prof Lemerle embraced the international opportunities that came her way.

"Mentors encouraged me to consider what's happening in the world, not just in NSW or Australia, around weed management," she said.

"I attended weed conferences around the world, developed good international networks, and became more involved with the Asian-Pacific Weeds Society, doing some collaborative work around post-graduate student supervision."

By the late 1980s, Prof Lemerle said herbicide resistance was rearing its head, and this is where her job changed direction.

"People called it the golden age of herbicides when everything worked really well, then we had resistance, and we had to look at more complex ways of managing weeds," she said.

"As herbicide resistance was taking off, and everybody was trying to address it, that was when my research changed from focusing on herbicides to looking at non-chemical weed control tactics, like crop competition, manipulating pre-sowing seedbanks, trying to stop weed seed set late in crops, and rotations to minimise herbicides."

Prof Lemerle was recognised for her teams' work and awarded the NSW Agriculture 'Outstanding Achievement' Award in 1996 and the Council of Australian Weed Science Societies Medal for 'Excellence in Weed Science' in 1998.

"These awards reflect the importance of building strong collaborative teams for successful research outcomes," she said.

"We recognised the importance of communicating about agriculture and our research to the wider community.

"Getting to the grand final of the ABC's New Inventors program in 2005 with the Stubble Star invention certainly helped elevate our profile. I still get people on the street asking about Stubble Star."

Prof Lemerle continued research but also moved into leadership roles in the late 1990s, including the leader of the Cropping Systems Program of the Cooperative Research Centre for Australian Weed Management and the inaugural director of the Graham Centre for Agricultural Innovation.

"I encourage early-career researchers to step up to opportunities as they arise; this can be challenging but is usually rewarding in the longer term," she said.

Prof Lemerle was selected to attend the Australia 2020 Summit representing Rural Industries and Rural Communities in April 2008. She also provided policy advice on various government committees.

In 2010, Prof Lemerle was part of the '10 Sisters' exhibit screened in the Australian Pavilion at the World Expo in Shanghai, China.

This featured her profile about R and D for food security and agricultural sustainability, and she travelled to China with the then Governor-General Quentin Bryce's 'Sisters' Delegation to represent Australia.

"A career in agricultural research can provide an amazing and surprising array of fascinating experiences," she said.

"However, this involves working closely with farmers, publishing scientific papers, getting research grants, managing teams, and communicating research outputs to the community and governments. It's not always easy, but I have found it a very rewarding career".

Following her retirement in 2015, Prof Lemerle became an Adjunct Professor with the Gulbali Institute at Charles Sturt University and a technical adviser and mentor supporting the Australian Volunteer Program (AVP), the Crawford Fund of Australia and the Australian Centre for International Research (ACIAR).

She became involved in capacity building and mentoring in Laos and Cambodia, focused on weed management in direct-seeded rice.

"Herbicide use in these countries was just starting, and we wondered if we could learn from the mistakes we made in Australia, to circumvent those mistakes, and retard the spread of herbicide resistance," she said.

Prof Lemerle said it's a fascinating time to work on pesticide use in South East Asia.

"How can we work with those countries and encourage them to work together? When they do that, they have much more leverage with big companies in getting good evaluations of chemicals as they come on the market," she said.

"These countries are moving from transplanted rice to drill-seeded rice because of labour shortages and the need for mechanisation, improved water use and efficiencies. They are moving to reduced-water cropping systems, and many of those systems are much more dependent on herbicides and a whole range of chemicals.

"I was working with farmers and advisors and two Australian AVP volunteers in Laos when COVID-19 took hold in 2020, and sadly, the work was cut short."

Prof Lemerle is currently a technical adviser on an ACIAR project through the University of Queensland, which is investigating non-chemical weed management in drill-seeded rice in Cambodia and Laos.

"This is an important project working with farmers, service providers and government agencies to develop sustainable rice production systems less dependent on herbicides," she said.

"Weed management requires a long-term approach and sufficient resources to achieve success. Developing trusting relationships between researchers and farmers also takes time and commitment."

Prof Lemerle believes ACIAR and Australian overseas volunteer programs play a critical role in improving food and nutrition security in our region.

"International development in biosecurity capacity building and sharing of knowledge and training provides warnings of early incursions and plays a critical role in reducing biosecurity risks to Australia and our neighbouring countries," she said.

"Another benefit is that we are supporting soft diplomacy, being good neighbours, and developing good relationships with people in various countries, which benefits our region."

She hopes to lead by example and encourage other retirees or people of any age to embrace international volunteering opportunities.

"It has been fantastic; when I was still working, I really loved my international collaborations, but since I retired at age 61, which is relatively early, I didn't want to stop doing things and waste my expertise," she said.

"It is satisfying working with the Crawford Fund and volunteers to provide technical support, mentor people, and supervise, as an energetic older person.

"It's an excellent way to mentor people and encourage them to work in international ag development.

"As a woman who has had a career in agriculture and continues with my activities, I hope I am encouraging other women to take leadership roles and work in international agriculture."

In 2023, Prof Lemerle was presented with the Lifetime Achievement Award at the 28th Asian-Pacific Weed Society Conference in Phuket.

"I was really proud, actually, and I don't usually say that," she said. "Some of our collaborators from Laos and Cambodia attended the conference, and I was proud to receive the award in front of them - that was the best part.

"In many countries in Asia and South East Asia, it's not easy for women. We started a Women In Weeds group in the Asian-Pacific Weeds Society to encourage women, so it's good for them to see a woman get an award."