There are Greens who espouse an "ecological Marxism" and claim that if Marx were around today he would support organic agriculture and a steady state economy based on renewable resources that provides everyone with "sufficiency". In such an economy the poor and rich countries would converge, with the former increasing somewhat and the latter shrinking a lot. The most notable exponent of this view is John Bellamy Foster, the editor of Monthly Review. (We will call him JBF for short.) He goes through the writings of Marx and tortures them until they turn green.
JBF draws our attention to a number of Marx's views that you could use to start building a case that he was a Green. Marx was concerned about the destruction of natural stocks of fertile soil, forests and fish needed by future generations. He also commented on how consumption often included frivolities that reflected people's alienation rather than real needs and that human thriving requires more than increased consumption. JBF also correctly points out that when Marx talked about mastering nature he did not mean destroying it but mastering its laws and harnessing it accordingly. However, from here on the case becomes rather shonky.
JBF tries to extract greenness from the fact that Marx was a materialist who believed we lived in a material world where we depended on plants and animals for food, water to drink and air to breathe. That is a long stretch.
The greening of Marx of course requires JBF to explain away how Marx and Engels talked about communism unleashing the productive forces. He claims this thoroughly ungreen viewpoint was confined to their youthful less mature writings. This is not true as the following quotes from the 1870s attest.
In Part 1of Marx's Critique of the Gotha Programme of 1875 we read:
Let us take, first of all, the words "proceeds of labor" in the sense of the product of labor; then the co-operative proceeds of labor are the total social product.
From this must now be deducted: First, cover for replacement of the means of production used up. Second, additional portion for expansion of production. Third, reserve or insurance funds to provide against accidents, dislocations caused by natural calamities, etc.
And further down in Part I we read:
In a higher phase of communist society, after the enslaving subordination of the individual to the division of labor, and therewith also the antithesis between mental and physical labor, has vanished; after labor has become not only a means of life but life's prime want; after the productive forces have also increased with the all-around development of the individual, and all the springs of co-operative wealth flow more abundantly -- only then then can the narrow horizon of bourgeois right be crossed in its entirety and society inscribe on its banners: From each according to his ability, to each according to his needs!
Then there is Engel's Anti-Duhring of 1877, the drafts of which were all discussed with Marx. Here we read:
The expansive force of the means of production bursts the bonds that the capitalist mode of production had imposed upon them. Their deliverance from these bonds is the one precondition for an unbroken, constantly accelerated development of the productive forces, and therewith for a practically unlimited increase of production itself. Nor is this all. The socialised appropriation of the means of production does away, not only with the present artificial restrictions upon production, but also with the positive waste and devastation of productive forces and products that are at the present time the inevitable concomitants of production, and that reach their height in the crises. Further, it sets free for the community at large a mass of means of production and of products, by doing away with the senseless extravagance of the ruling classes of today and their political representatives. The possibility of securing for every member of society, by means of socialised production, an existence not only fully sufficient materially, and becoming day by day more full, but an existence guaranteeing to all the free development and exercise of their physical and mental faculties — this possibility is now for the first time here, but it is here.
JBF also has to misconstrue Marx's constant reference to the fact that capitalists are compelled by the forces of competition to accumulate in order to survive, by suggesting that he actually disapproved of the process. For Marx the plowing back of much of the surplus value rather than spending it all on extravagant consumption was what made capitalism superior to previous societies where there was a compulsion to stagnate. Capitalism was compelled by its nature to deliver economic and social progress.
JBF's specialty is his "metabolic rift" which he attributes to Marx. It picks up on Marx's analysis of the contradiction between town and country. Marx saw how industrialization led to the movement of an increasing proportion of the population into cities and this meant a break in the nutrient cycle as human waste and food scraps were not returned to the farm but instead dumped in rivers and oceans. To make up for this we have now become dependent on finite supplies of synthetic fertilizer which leach all over the place causing pollution.
Anyone who has read Marx cannot possibly believe that Marx considered a return to the countryside as the solution. I have no trouble imagining Marx looking to "industrial" agriculture under communism, where a small workforce with ever more machinery and precision farming methods would nurture the soil and deliver ever higher yields. They could recycle nutrients if need be. Although we are not about to run out of the "unnatural" sources any time soon.
In my view the bottom line here is that if you are an opponent of economic growth you cannot claim that Marx is one of your own.