The motivations of the planters varied greatly. The large plantations were established to make money; some of them were publicly traded companies, and their investors had invested in order to make money. At the other end of the scale were small planters. Some of them were already in PNG as traders, and established small plantations as side-businesses. Others moved to PNG for a variety of reasons, with only one of them being to make money. Some went there with the expectation, or at least hope, of becoming rich. Others went there for adventure, to start a new life, to escape poverty in Australia, or to escape arrest in Australia. For the small planters, it was an opportunity for a new start that required very little capital - leasehold land was available very cheaply.

Some planters were as exploitative as possible (more on which below). Some had genuine concern for their workers (even if often paternalistic and racist). There were two important factors which greatly limited exploitation: the colonial administration and PNG itself.

First, the colonial administration (Australian since Federation, and the British protectorate and colonial administrations before then) gave substantial protection to Papuan workers and supported Papuan land rights. I find this truly remarkable considering the disregard for indigenous land and labour rights in Australia, especially in the individual colonies before federation. The colonial administration largely refused applications for purchase and lease of excessive amounts of land (basically, those requests smelled of land speculation rather than any intent to make "proper" use of the land).

Papuan workers rights were supported by the administration. Plantation owners and white plantation workers could be and were sometimes fined or imprisoned for physical and/or financial mistreatment of workers. Workers were usually employed under indentures, contracts for a specified period of time (the most common periods varied from 3 months to 3 years, over time). The administration specified the minimum conditions required (e.g., the maximum hours of work that could be demanded, no work on Sundays, the minimum amounts of food that had to be provided, etc.). The administration strove to make sure that workers understood their contracts and conditions (and deceptive contracts would be cancelled). The administration also limited the number of Papuans who could be employed under indentures to a level at which they felt would not disrupt Papuan society (the demand for labour never reached this limit, so this "protection" wasn't needed). This contrasts strongly with the treatment of indentured Melanesian labour ("kanakas") in Queensland, which was based on exploitation, deception, and outright kidnapping. Papuan labour was only briefly exported to Queensland before it was banned. Notably, the captain of the first "recruiting" ship (in 1883) was later charged and convicted for kidnapping in Queensland (and to the shame of the Queensland government, that captain was also a Queensland government agent).

Second, most Papuans were subsistence farmers. They did not need paid employment to earn a living. The attraction of employment was earning money to buy things such as steel axes, knives, and luxury goods. This, as in other places where most workers were subsistence farmers, had both good and bad effects. Generally, because paid employment was not necessary, workers were not willing to work under poor conditions (e.g., too-long hours of work per day). Employers who mistreated workers could find themselves with no workers. Workers could also readily desert their contracts simply by walking home (something not possible for kanakas in Queensland). If the administration felt that their desertion was justified by poor working conditions, the administration could and did cancel the contracts and force pro rata payment of the owed wages. Plantation employment was not the only way in which Papuans could earn money. They could, and sometimes did, plant their own rubber trees or extra coconut trees to produce copra for sale.

The disadvantage of subsistence-farmer labour is low wages. Since the workers don't need to earn a living wage, wages are often below the subsistence level. For example, in the late 19th century and early 20th century, the wages were often only about about 1/4 or 1/5 of the total expense of employing Papuans - the cost of food, transport, and recruiting was much greater. This leads to a cycle where the low wages mean that only subsistence farmers will seek employment, which in turn keeps wages low.

There were exceptions to these low wages. One ongoing problem that employers had was high turnover of workers. (If a worker works to earn the money to buy a steel axe, and then buys that steel axe, why will he work again until he need a new axe?) This limited the skill and experience of the workforce (which hurt the productivity of rubber plantations). Skilled and experienced workers, who could be very valuable for training the new workers, often asked for, and often received substantially higher wages, with some even earning over half of what white employees earned (if food and keep was included). Of course, this highlights the general inequality of pay - if the highest earning Papuans earn half of what the lowest paid white workers earn, the system is far from fair.

For further reading on plantations, Papuan labour, and the administration up to World War II, see

• D. C. Lewis, Plantation Dream - Developing British New Guinea and Papua 1884-1942, Journal of Pacific History, Australian National University, 1996

which is freely available at: https://openresearch-repository.anu.edu.au/bitstream/1885/132636/1/JPH_Plantation_Dream.pdf

While the administration was helpful in protecting Papuan labour and land rights, they were content to stop at protection. Economic development, education, modernisation, etc. were non-issues until after World War II, when finally there was a start to preparing Papua for eventual independence. Independence would need educated Papuans, and finally schools were established. For more on this post-war period, see

• Ernest John Meredith Steel, Australian Policy Implementation in Papua New Guinea 1945-1953, MA thesis, University College, University of New South Wales, Australian Defence Force Academy, 1989. http://unsworks.unsw.edu.au/fapi/datastream/unsworks:54141/SOURCE01?view=true

and my past reply to a question about PNG independence in

• https://www.reddit.com/r/AskHistorians/comments/n03r24/why_did_australia_lose_papua_new_guinea/

In the early 20th century (especially 1910-1920), the rubber industry appeared to be a future bonanza, and investment was heavy. Much of this investment was in Malaya and Indonesia, with only tiny investment in New Guinea (the Germans in German New Guinea (which came under Australian control after WWI) made the mistake of planting the commercially-inferior Ficus elastica (Assam rubber) rather than Hevea brasiliensis which hampered the development of the rubber industry in that region). By the 1930s, it became apparent that there had been over-investment in the industry (which took time to have an impact, since trees take about 6 years before they can be tapped), and the more mature SE Asian industry was outcompeting PNG rubber. The SE Asian industry also benefited from high labour productivity, in part due to importation of Indian and Chinese labour - these workers could not readily desert, and worked longer hours than Papuan workers because they were doing it to avoid crushing poverty at home.

Some Papuan planters lobbied the administration to be allowed to import Indian, Chinese, or Javanese labour. The administration allowed the entry of skilled Javanese workers, for the purpose of instructing Papuan workers, e.g., in the operation of machinery in the copra industry. The widespread importation of Indian and Chinese labour was not allowed for multiple reasons: (a) it was felt that it would disprupt Papuan society, (b) it would make Papuans lazy (some administrators felt that such imported labour had made ethnic Malays in Malaya lazy), and (c) PNG was Australian territory, and such non-white people should not be allowed into PNG (while it wasn't the Australian mainland, it was Australian and all too close to the mainland).

After WWII, there was renewed interest in rubber. The Korean War (in which Australia was involved) reminded Australia that rubber was an important strategic resource, and Australia supported the Papuan rubber industry by paying above-world-market prices. The move towards independence had seen steps towards economic support for Papuans, in the form of cooperative to allow small copra and rubber producers to sell their products more easily. As a result of these two factors, village production of rubber grew, while plantation production largely stagnated. In the 1980s, many rubber plantations switched to other more profitable products (notably, beef), while village rubber continued to grow.